THE STATE OF ILLINOIS, PETITIONER V. LANCE GATES, ET UX. No. 81-430 In the Supreme Court of the United States October Term, 1982 On Writ of Certiorari to the Supreme Court of Illinois Supplemental Brief for the United States as Amicus Curiae Supporting Reversal TABLE OF CONTENTS Interest of the United States Summary of argument Argument: I. As a judicially created rule of evidence, the exclusionary rule may appropriately be modified in the light of reason and experience A. The only viable justification for the exclusionary rule is its presumed deterrent effect on unlawful police conduct B. The policy of deterrence dictates a cost-benefit approach to the application of the exclusionary rule II. The costs of the exclusionary rule outweigh its benefits when it is applied to suppress evidence obtained in the reasonable good-faith belief that the search and seizure in question did not violate the Fourth Amendment A. The presumed benefits of the exclusionary rule are not realized by applying it to suppress evidence obtained in the good-faith belief that the Fourth Amendment has not been violated B. The reasons for applying the exclusionary rule are most remote when law enforcement officers have relied in good faith on a judicially-issued search warrant C. In light of the exclusionary rule's inability to fulfill its deterrent purpose when applied to honest mistakes, its costs are higher than our system of criminal justice can afford D. The objections to a good-faith exception to the exclusionary rule are insufficient to overcome the need for modification Conclusion QUESTION PRESENTED Whether the Fourth Amendment exclusionary rule should be modified so as not to bar the admission of evidence obtained in the good faith, reasonable belief that the search and seizure at issue did not violate the Fourth Amendment. INTEREST OF THE UNITED STATES The Court has requested supplemental briefing on the question whether the rule requiring the exclusion of evidence obtained in violation of the Fourth Amendment, which was first announced and applied to federal prosecutions in Weeks v. United States, 232 U.S. 383 (1914), should be modified. Few issues in the area of criminal law are of more profound importance to the United States. On the practical level, questions regarding the proper interpretation of the Fourth Amendment and the concomitant application of the exclusionary rule are at the heart of countless federal prosecutions. And on the policy level, the extent to which the exclusionary rule is appropriately invoked is central to the fair and efficient administration of criminal justice. Accordingly, the United States has as substantial an interest in the outcome of this case as if it were a party. SUMMARY OF ARGUMENT 1. Nothing in the Fourth Amendment or any other provision of the Constitution either directly or implicitly provides for the exclusion of illegally seized evidence from criminal trials. Instead, decisions of this Court over the last decade have made it clear that the exclusionary rule first enunciated in Weeks v. United States, 232 U.S. 383 (1914), and later extended to the states in Mapp v. Ohio, 367 U.S. 643 (1961), is a judicially-created remedy, the paramount and perhaps sole purpose of which is the deterrence of unlawful police conduct. See, e.g., United States v. Calandra, 414 U.S. 338, 348 (1974); Desist v. United States, 394 U.S. 244, 254 n.24 (1969). As the deterrence rationale has achieved supremacy over earlier, now-discarded justifications for the rule, the Court has recognized that it makes sense to apply the rule only to those situations in which its deterrent purpose will in fact be significantly advanced. Calandra, 414 U.S. at 348. Accordingly, the Court now employs a cost-benefit analysis whenever it considers whether the rule should be applied to particular situations. When the costs of applying the rule are found to outweigh whatever deterrent effect it might achieve, the rule will not be imposed. See, e.g., United States v. Havens, 446 U.S. 620 (1980); United States v. Ceccolini, 435 U.S. 268 (1978); Stone v. Powell, 428 U.S. 465 (1976); Calandra, 414 U.S. 338; Alderman v. United States, 394 U.S. 165 (1969). 2. After nearly 70 years of experience with the exclusionary rule, it is now appropriate to apply the same type of cost-benefit analysis in considering whether to adopt a "reasonable good-faith" exception to the existing rule. If, as we shall demonstrate in this brief, the benefits of applying the rule to certain classes of situations are outweighted by the costs, the Court should not hesitate to reformulate the rule. In our submission, a reasoned cost-benefit analysis of the exclusionary rule compels the conclusion that it should no longer be applied in those situations in which evidence is obtained in the reasonable good-faith belief that the search and seizure in question did not violate the Fourth Amendment, even if that belief later proves to have been mistaken. Preliminarily, however, we suggest that this is a situation ill-suited to a strictly even-handed weighing of costs and benefits. By excluding unquestionably relevant evidence, the exclusionary rule operates in precisely the opposite manner from what we demand of other rules of evidence. Thus, its benefits should not simply be presumed; they must, instead, be convincingly demonstrated if they are to overcome the indisputable costs. Accordingly, the exclusionary rule cannot rationally be retained in those circumstances where it is thought simply that it might produce some benefit. Similarly, the rule should not be retained merely because it appears that no better deterrent to police misconduct currently exists; the rule must carry its own weight through demonstrable evidence that it operates in the manner intended. a. The principal benefit claimed for the exclusionary rule is its deterrent effect. Unfortunately for the proponents of the rule, however, its deterrent effect has never been proven by empirical evidence. And even if one accepts the intuitively plausible but unproven assumption that the rule is capable of deterring police misconduct to some extent, it is readily apparent as a matter of logic that the deterrent potential of the rule is drastically reduced, if not wholly eliminated, when it is invoked to suppress evidence obtained by a reasonably well-trained police officer in the belief that his conduct did not violate the Fourth Amendment. The ineffectiveness of the rule as a deterrent device is particularly evident in cases such as the instant one, where police officers have done exactly what is demanded of them by obtaining a judicial search warrant and acting according to its terms. It is irrational to assume that police officers can be meaningfully deterred from future "unlawful" conduct when, at the time of the conduct in question, they had the authorization of a warrant obtained in the reasonable good-faith belief that there existed probable cause for the search and seizure in question. As has been often noted, the suppression of evidence that occurs when a higher court overturns a magistrate's finding of probable cause does not involve any police misconduct that needs to be deterred; all that is involved is disagreement among judges about subtle and ever-changing principles of law. There is no rational justification for applying the exclusionary rule to these situations, which bear not the slightest relationship to the egregious police misconduct for which the rule was first devised. b. The presumed benefits of the exclusionary rule, which are virtually nonexistent in cases like the instant one, must be weighed against the rule's undeniable costs. Those costs are readily catalogued: First, the exclusionary rule eliminates from consideration at trial the very type of evidence that is most relevant and trustworthy. The resulting distortion of the truth-finding process of adversary adjudication requires justification of the highest order. Second, the rule benefits only those who otherwise would be found guilty; it allows "(t)he criminal * * * to go free because the constable has blundered." People v. Defore, 242 N.Y. 13, 21, 150 N.E. 585, 587. cert. denied, 270 U.S. 657 (1926). The available data demonstrate that the rule has a significant effect on the prosecution's ability to obtain convictions. Moreover, the effects of the rule are felt most heavily in drug cases involving defendants who, following dismissal of their narcotics charges because of the suppression of dispositive evidence, often go on to commit other crimes, frequently crimes of violence. The rule affords no remedy, however, for the innocent victims of unlawful police conduct, who are or should be the very persons most deserving of protection. Third, and irrespective of the actual number of guilty defendants set free by virtue of the rule, its application necessarily exacts a high cost in diminished public respect for the judicial system. The public perception that there is something wrong with a system of criminal justice that frees guilty defendants on "technicalities" cannot lightly be ignored. Fourth, and of particular relevance to the instant case, the rule lacks the essential ingredient of proportionality. It utterly fails to take into account the actual existence of police misconduct that is perceived as such by the public and that is within the ambit of the proscriptions intended by the Framers of the Fourth Amendment. Behavior that a reasonably well-trained officer could not possibly be expected to know violated the Fourth Amendment is subject to the same Draconian "remedy" as the most flagrant abuse of police power. Fifth, even granting for purposes of argument the premise that application of the rule to conduct close to the often indistinct boundary between lawful and unlawful searches would meaningfully deter some marginally improper police conduct (see United States v. Johnson, No. 80-1608 (June 21, 1982), slip op. 23-24), in this class of cases the rule is, almost by definition, as likely to deter proper as improper conduct. Thus, one of the gravest costs of relentless application of the rule to honest police mistakes is not merely that "the criminal * * * (shall) go free because the constable has blundered," but that the crime shall go undetected (or, worse, unprevented) because the exclusionary rule has deterred the officer from the lawful performance of his duties. Sixth, the present rule places tremendous strains on the judicial system by encouraging the filing of suppression motions irrespective of whether there is even the slightest evidence of serious police misconduct. The windfall benefits of the rule to the guilty defendant are so overwhelming as to completely negate the process of self-screening and evaluation on the part of criminal defense counsel. A country whose judicial system is as seriously overloaded as ours can ill-afford the continued application of a rule that fosters such vast amounts of make-work. Finally, the rule actually diminishes the Fourth Amendment by making judges reluctant to condemn questionable practices because of the extreme consequences -- total suppression of unquestionably relevant and frequently dispositive evidence. c. The practical details relating to the operation of a "good faith" exception to the exclusionary rule are best left to future cases and initial development by lower courts. For now, it is sufficient to note that the most commonly-voiced objections to a good faith exception are lacking in substance. For example, it has been claimed that the exclusionary rule operates to ensure thorough police training in the requirements of the Fourth Amendment. But this benefit would not be lost by the adoption of a good-faith exception to the rule. Such an exception would not "put a premium on ignorance" because the reasonableness of a police officer's actions would be tested by the objective standard of what should be expected of the reasonably well-trained law enforcement official. Thus, a good-faith exception would preserve every incentive for police departments to ensure that their officers remain current with the development of Fourth Amendment law; indeed, the incentive for high-quality training might prove to be greater than it is now because the quality of police training could be an important factor in evaluating the reasonableness of a questioned search and seizure. Moreover, the objective nature of the inquiry will protect the judicial system against unduly burdensome and generally irrelevant inquiries into the subjective state of mind of a particular officer. In most cases, a court will need to determine only whether a reasonably well-trained police officer should have known, in light of the extant principles of law, that his conduct was prohibited. The inquiry will thus not be markedly different from that required of a court in deciding a suppression motion. It is also sometimes suggested that the exclusionary rule needs to be retained in its present form, or even expanded, so as not to "freeze" the development of Fourth Amendment law. Of course, it is not entirely clear that society is greatly benefited by having courts continue to decide every question that inventive lawyers can devise, particularly when "the general principles applicable to claims of Fourth Amendment violations are well settled * * * ." Arkansas v. Sanders, 442 U.S. 753, 757 (1979). But, in any event, there need be no serious concern that adoption of a good-faith exception to the exclusionary rule would bring a halt to the adjudication of substantive Fourth Amendment issues. As demonstrated by the number of nonmeritorious suppression motions currently filed, criminal defendants can be counted upon to assert every defense available to them. Because the substantial windfall of exclusion would remain available to those defendants who could show unreasonable police conduct, it is unrealistic to assume that defendants with colorably meritorious claims of Fourth amendment violations will lose their incentive to litigate (although we anticipate that there would be a considerable reduction in the number of frivolous claims). There is, moreover, no jurisprudential impediment to a court's deciding a question of substantive Fourth Amendment law before determining the applicability in a particular case of a good-faith exception to the exclusionary rule. Whether to assume the existence of a Fourth Amendment violation and decide only the question of good faith, or whether to decide the substantive question first, should be left to judicial discretion. It might well be appropriate for courts to decline to adjudicate nonrecurring fact-bound questions concerning the propriety of a particular search and seizure if application of a good-faith exception would be sufficient to dispose of the case. On the other hand, courts would remain free to decide significant unsettled questions of law or to adjudicate particularly problematic or recurring factual situations that give cause for concern. Finally, it has been suggested that, whatever, the flaws of the exclusionary rule, it must be retained because there is no adequate alternative. This is, we submit, insufficient justification for a rule that carries the heavy costs of the exclusionary rule. Moreover, the continued existence of the rule may well operate to deter the development of more efficacious and less costly alternatives. Accordingly, the time has come for recognition by this Court that, at least in the case of reasonable good-faith violations of the Fourth Amendment, the exclusionary rule is entirely unjustified, if not actually detrimental to the achievement of the goals of the Fourth Amendment. ARGUMENT I. AS A JUDICIALLY CREATED RULE OF EVIDENCE, THE EXCLUSIONARY RULE MAY APPROPRIATELY BE MODIFIED IN THE LIGHT OF REASON AND EXPERIENCE This Court first required the exclusion of evidence obtained by federal agents in violation of the Fourth Amendment in Weeks v. United States, 232 U.S. 383 (1914), a case involving successive, warrantless searches of an accused's home that resulted in the seizure of letters and other personal documents. Later, in Mapp v. Ohio, 367 U.S. 643 (1961), the Court extended the application of the Fourth Amendment exclusionary rule to the states in the context of a case involving a forcible, warrantless entry into a suspect's home that was followed by an exploratory search through personal papers and effects. Since that time, however, the exclusionary rule has been increasingly criticized as "both conceptually sterile and practically ineffective in accomplishing its stated objective" of insuring compliance with the Fourth Amendment by law enforcement officials. Bivens v. Six Unknown Named Agents of Federal Bureau of Narcotics, 403 U.S. 388, 415 (1971) (Burger, C.J., dissenting). Accordingly, members of the Court have repeatedly urged a general reconsideration of the exclusionary rule and the situations in which it is applied. Id. at 415-416, 420-421; see also Robbins v. California, 453 U.S. 420, 437, 443-444 (1981) (Rehnquist, J., dissenting); California v. Minjares, 443 U.S. 916, 917 (1979) (Rehnquist, J., dissenting from denial of stay); United States v. Ceccolini, 435 U.S. 268, 283 (1978) (Burger, C.J., concurring); Brewer v. Williams, 430 U.S. 387, 413-414 n.2 (1977) (Powell, J., concurring); Stone v. Powell, 428 U.S. 465, 496 (1976) (Burger, C.J., concurring); id. at 537-539 (White, J., dissenting); Schneckloth v. Bustamonte, 412 U.S. 218, 271 (1973) (Powell, J., concurring); Coolidge v. New Hampshire, 403 U.S. 443, 490 (1971) (Harlan, J., concurring). The instant case offers an appropriate vehicle for such a reevaluation of the exclusionary rule. As we set out in our initial brief in this case (Gov't Br. 2-5), the police officers here obtained a search warrant after making a detailed submission to a state court judge based on both an anonymous tip and corroborating information obtained by investigation of the tip. Thereafter, the officers executed the warrant according to its terms. Assuming, arguendo, that the courts below correctly held that the search warrant was supported by less than probable cause, the officers' conduct here nevertheless stands on a far different footing from the warrantless and palpably unlawful searches at issue in Weeks and Mapp. The suppression remedy does not meaningfully protect against the arbitrary invasion of privacy interests -- the core value safeguarded by the Fourth Amendment -- when, as here, law enforcement officers have acted in the reasonable, good-faith belief that their conduct complies with constitutional standards. Modification of the exclusionary rule to acknowledge this point is consistent with the fundamental purpose of the rule and the cases of this Court explicating it. A. The Only Viable Justification For The Exclusionary Rule Is Its Presumed Deterrent Effect On Unlawful Police Conduct Nothing in the Fourth Amendment or any other provision of the Constitution either directly or implicitly provides for the exclusion of illegally seized evidence from criminal trials. Although the plurality opinion in Mapp, 367 U.S. at 649, 651, 655-656, suggested that an absolute exclusionary rule is constitutionally required, the Court has never so held. Nevertheless, because the exclusionary rule was first conceived in the context of flagrantly unlawful police conduct and later extended to the states in a case involving even more abusive practices, it is not surprising that, for many years, the Court appeared to assume that the Fourth Amendment required an absolute prohibition against the use of illegally obtained evidence. As the Court has come to focus more clearly on the true purpose of the exclusionary rule and the effect it is likely to have in differing contexts, however, it has recognized that the rule is merely a judge-made rule of evidence -- constitutionally based but not specifically constitutionally required -- the contours of which must be varied to fit the circumstances. See, e.g., United States v. Calandra, 414 U.S. 338, 348 (1974); Desist v. United States, 394 U.S. 244, 254 n.24 (1969); see also Stone v. Powell, 428 U.S. at 542 (White, J., dissenting); Wolf v. Colorado, 338 U.S. 25, 39-40 (1949) (Black, J., concurring) (rule "is a judicially created rule of evidence"). /1/ Accordingly, the exclusionary rule "has never been interpreted to proscribe the introduction of illegally seized evidence in all proceedings or against all persons." Stone v. Powell, 428 U.S. at 486. Because of the inherent trustworthiness of seized tangible evidence and the resulting societal costs from its loss through suppression, application of the exclusionary rule has been carefully "restricted to those areas where its remedial objectives are thought most efficaciously served." Calandra, 414 U.S. at 348. Thus, any consideration of the extent to which the rule should be modified must begin with a clear understanding of its purpose. Over time, the justifications advanced in support of the exclusionary rule have varied, but it is now clear that the principal, and certainly the only logical purpose of the rule is to deter Fourth Amendment violations by law enforcement officers by removing the incentive to commit those violations. See, e.g., Stone v. Powell, 428 U.S. at 486; United States v. Janis, 428 U.S. 433, 446 (1976). The Court summarized the rule's deterrent purpose succinctly in Elkins v. United States, 364 U.S. 206, 217 (1960): The rule is calculated to prevent, not to repair. Its purpose is to deter -- to compel respect for the constitutional guaranty in the only effectively available way -- by removing the incentive to disregard it. The rise to preeminence of the exclusionary rule's deterrent purpose reflects the abandonment of earlier justifications. Initially, the rule was justified as a remedy for the violation of an accused's personal Fourth Amendment right of privacy. Weeks, 232 U.S. at 398. This rationale was difficult to maintain, however, because the exclusionary "remedy" is simply incapable of redressing invasions of privacy (Calandra, 414 U.S. at 347): The purpose of the exclusionary rule is not to redress the injury to the privacy of the search victim: "(The) ruptured privacy of the victims' homes and effects cannot be restored. Reparation comes too late." Linkletter v. Walker, 381 U.S. 618, 637 (1965). Moreover, as a remedy for unlawful invasions of privacy, the exclusionary rule is fundamentally irrational because of the haphazardness surrounding its application -- only guilty defendants are afforded the benefits of the remedy -- and because, as Judge Friendly has observed, "the benefit received (exclusion of evidence proving the defendant's guilt) is wholly disproportionate to the wrong suffered." Friendly, The Bill of Rights as a Code of Criminal Procedure, 53 Calif. L. Rev. 929, 951 (1965). Another early rationale for the exclusionary rule was that it served to safeguard the purity of the courts' processes by forbidding the introduction of tainted evidence. See Elkins, 364 U.S. at 222-223. But the " 'imperative of judicial integrity' " has not in fact served as the basis for deciding cases. Oaks, Studying the Exclusionary Rule in Search and Seizure, 37 U. Chi. L. Rev. 665, 669 (1970). The Court has recognized that the strength of this rationale has been steadily eroded by a series of decisions permitting the collateral use of unlawfully seized evidence. See pages 15-18, infra. Thus, preserving the courts' distance from tainted evidence has now been eclipsed by, and indeed subsumed within, the policy of deterrence: to the extent that the judicial integrity rationale was intended to insulate the courts from lawless governmental conduct, that function is fully served by the policy of deterrence. See Janis, 428 U.S. at 458-459 n.35; Stone v. Powell, 428 U.S. at 484-485; United States v. Peltier, 422 U.S. 531, 536-538 (1975). But even if the " 'imperative of judicial integrity' " had survived as an independent justification for the exclusionary rule, it would not be impugned by the good-faith exception we propose (see pages 24-25 & n.7, infra). As the Court recognized in Peltier, 422 U.S. at 537-538, "the 'imperative of judicial integrity' is * * * not offended if law enforcement officials reasonably believed in good faith that their conduct was in accordance with the law even if decisions subsequent to the search or seizure have held that conduct of the type engaged in by the law enforcement officials is not permitted by the Constitution." Indeed, we suggest that judicial integrity is put in greater jeopardy by the rendition of erroneous verdicts caused by the suppression of dispositive evidence than it is by the admission of evidence that a reasonably well-trained police officer could not have been expected to know was being obtained in violation of the Fourth Amendment. B. The Policy Of Deterrence Dictates A Cost-Benefit Approach To The Application Of The Exclusionary Rule Recognition that the policy of deterrence is the only logical justification for the exclusionary rule has governed the Court's consideration of a multitude of applications of the rule. For more than a decade, the Court has engaged in a cost-benefit analysis whenever it has confronted suggested expansions of the rule or has examined afresh the propriety of certain applications of the rule. For example, in Alderman v. United States, 394 U.S. 165, 174-175 (1969), the Court ruled that suppression may be sought only by one whose own Fourth Amendment rights have been violated. The Court concluded that any additional benefits that might flow from extending the suppression remedy to persons not themselves the victims of unlawful searches and seizures were offset by "the public interest in prosecuting those accused of crime and having them acquitted or convicted on the basis of all the evidence which exposes the truth." Id. at 175. See also United States v. Salvucci, 448 U.S. 83, 94-95 (1980); Rawlings v. Kentucky, 448 U.S. 98, 104-106 (1980); United States v. Payner, 447 U.S. 727, 731-734 (1980); Rakas v. Illinois, 439 U.S. 128, 137 (1978). /2/ Similarly, the Court's recognition of the permissible use of unlawfully seized evidence as an impeachment tool rests on the conclusion that any furthering of the deterrent purpose of the exclusionary rule would be more than offset by the interference with the truth-finding function of criminal trials. See United States v. Havens, 446 U.S. 620 (1980); Walder v. United States, 347 U.S. 62 (1954); see also Oregon v. Hass, 420 U.S. 714 (1975); Harris v. New York, 401 U.S. 222 (1971). In reaching this conclusion, the Court noted in Havens that any increase in deterrence occasioned "by forbidding impeachment of the defendant who testifies (is) deemed insufficient to permit or require that false testimony go unchallenged, with the resulting impairment of the integrity of the factfinding goals of the criminal trial" (446 U.S. at 627). Likewise, the Court has refused to apply the exclusionary rule when the initial illegality has become attenuated. E.g., United States v. Ceccolini, 435 U.S. at 280. Again, a cost-benefit analysis controlled the outcome of the case (ibid.): Application of the exclusionary rule in this situation could not have the slightest deterrent effect * * *. The cost of permanently silencing (a live witness) is too great for an evenhanded system of law enforcement to bear in order to secure such a speculative and very likely negligible deterrent effect. The Court also has employed a cost-benefit analysis in determining whether to apply the exclusionary rule to various types of proceedings other than the criminal trial itself. In Calandra, the Court refused to prohibit the use of illegally seized evidence in grand jury proceedings. In reaching this result, the Court stated (414 U.S. at 351-351; footnote omitted): Any incremental deterrent effect which might be achieved by extending the rule to grand jury proceedings is uncertain at best. * * * We therefore decline to embrace a view that would achieve a speculative and undoubtedly minimal advance in the deterrence of police misconduct at the expense of substantially impeding the role of the grand jury. A like analysis was employed in Stone v. Powell, 428 U.S. at 482-495, where the Court held that the substantial costs to society of the suppression remedy would outweigh any marginal deterrent effect that might follow from permitting state prisoners to relitigate search and seizure claims in federal habeas corpus proceedings. And in Janis, 428 U.S. at 454, the Court concluded that "exclusion from federal civil proceedings of evidence unlawfully seized by a state criminal enforcement officer has not been shown to have a sufficient likelihood of deterring the conduct of the state police so that it outweighs the societal costs imposed by the exclusion." Finally, the Court has employed the same balancing analysis when considering whether Fourth Amendment decisions should be applied retroactively. See, e.g., Peltier, 422 U.S. at 538-539; Williams v. United States, 401 U.S. 646, 654-655 (1971) (plurality opinion); Desist v. United States, 394 U.S. at 249-250; Linkletter v. Walker, 381 U.S. 618, 636-639 (1965). /3/ In these cases, the Court has recognized that retroactive application of new Fourth Amendment standards cannot meaningfully promote the deterrent purpose of the exclusionary rule. In short, the Court has steadfastly declined to apply the exclusionary rule in circumstances in which the degree of incremental deterrence that suppression might provide is outweighed by the attendant societal costs. /4/ This cost-benefit approach is a necessary corollary to the fact that deterrence is the only logical justification for the rule. II. THE COSTS OF THE EXCLUSIONARY RULE OUTWEIGH ITS BENEFITS WHEN IT IS APPLIED TO SUPPRESS EVIDENCE OBTAINED IN THE REASONABLE GOOD-FAITH BELIEF THAT THE SEARCH AND SEIZURE IN QUESTION DID NOT VIOLATE THE FOURTH AMENDMENT After nearly 70 years of experience with the exclusionary rule, it is now appropriate for the Court to employ the same type of cost-benefit analysis utilized in the past in evaluating various applications of the rule (see pages 15-18, supra) to a consideration of the wisdom of its application to reasonable good-faith mistakes. Preliminarily, however, we suggest that this weighing is not properly performed on scales that are evenly balanced. By excluding unquestionably reliable and relevant evidence, the exclusionary rule operates in precisely the opposite manner from what we generally demand of other rules of evidence. See, e.g., C. McCormick, Handbook of the Law of Evidence Section 72 (E. Cleary ed. 1972). Thus, the rule's benefits should not simply be presumed; the rule's retention requires more than an assumption that it might have the desired deterrent effect. As the Chief Justice observed in his concurrence in Stone v. Powell, 428 U.S. at 499-500: To vindicate the continued existence of this judge-made rule, it is incumbent upon those who seek its retention * * * to demonstrate that it serves its declared deterrent purpose and to show that the results outweigh the rule's heavy costs to rational enforcement of the criminal law. * * * The burden rightly rests upon those who ask society to ignore trustworthy evidence of guilt, at the expense of setting obviously guilty criminals free to ply their trade. See also Wilkey, The Exclusionary Rule: Costs and Viable Alternatives, 1 Crim. Just. Ethics 16, 20 (1982). In any event, as we shall now demonstrate, such an analysis reveals that the costs of the rule far outweigh its presumed benefits when applied to reasonable police actions undertaken in good faith, particularly in a case such as the instant one. Accordingly, the Court should have no hesitation in fashioning appropriate exceptions to the rule. A. The Presumed Benefits Of The Exclusionary Rule Are Not Realized By Applying It To Suppress Evidence Obtained In The Good-Faith Belief That The Fourth Amendment Has Not Been Violated 1. The principal benefit claimed for the exclusionary rule is its deterrent effect. Unfortunately for the rule's proponents, however, its deterrent effects have never been proven. The Court itself has acknowledged the lack of reliable empirical evidence to support the deterrent effect of the exclusionary rule. In Wolf v. Colorado, 338 U.S. 25, 44 n.5 (1949) (Murply, J., dissenting), Justice Murphy argued that his own "statistical study" of police chiefs supported a broadened application of the rule. /5/ Several years later, however, the Court observed that "(t)here is no reliable evidence known to us that inhabitants of those states which exclude the (tainted) evidence suffer less from lawless searches and seizures than those of states that admit it." Irvine v. California, 347 U.S. 128, 136 (1954). See also Elkins, 364 U.S. at 218 ("it cannot positively be demonstrated that enforcement of the criminal law is either more or less effective under either rule"). Since Mapp, of course, there have been no meaningful comparative statistics showing the effect the exclusionary rule has had upon police conduct. See Janis, 428 U.S. at 452 & n.24. The Court has noted twice in recent years that the available empirical studies are virtually useless. Stone v. Powell, 428 U.S. at 492 & n.32; id. at 498-499 (Burger, C.J., concurring); Janis, 428 U.S. at 449-453. This situation is not surprising in view of the manifest difficulty of designing and implementing an adequately controlled comparative study that could produce objectively valid results. The commentators, like this Court, have concluded that there is no reliable evidence to support the proposition that the exclusionary rule operates effectively to deter police misconduct. The author of the leading empirical study on the question has concluded (Oaks, supra, 37 U. Chi. L. Rev. at 755): As a device for directly deterring illegal searches and seizures by the police, the exclusionary rule is a failure. There is no reason to expect the rule to have any direct effect on the overwhelming majority of police conduct that is not meant to result in prosecutions, and there is hardly any evidence that the rule exerts any deterrent effect on the small fraction of law enforcement activity that is aimed at prosecution. What is known about the deterrent effect of sanctions suggests that the exclusionary rule operates under conditions that are extremely unfavorable for deterring the police. The harshest criticism of the rule is that it is ineffective. Thus, the rule cannot be reliably shown to fulfill the only purpose that justifies its implementation. And even if one grants the intuitively plausible but not empirically demonstrated premise that suppression of evidence in a criminal trial can to some extent or in some circumstances deter law enforcement officers from violations of the Fourth Amendment, then it sensibly follows that the degree of deterrence achieved is likely to vary in relation to two factors: the extent to which imposition of the suppression sanction is "painful," and the extent to which the officer can predict at the time he acts that his action is improper and therefore likely to lead to imposition of the sanction. Cases such as Calandra, Stone v. Powell, Janis and Havens turn upon the Court's assessment of the first of these factors; they reach the result they do because it appeared sufficiently unlikely to the Court that police officers would be encouraged to engage in prohibited conduct by the availability of the particular uses of unlawfully seized evidence there permitted that any speculative deterrent effect was clearly outweighed by the evident costs of suppression. The present case calls upon the Court to evaluate the second factor, i.e., whether deterrence will be too slight to justify the costs of suppression when the conduct in question is of a sort that a reasonably well-trained officer would not recognize to be unlawful. In advancing the contention that exclusion of evidence is unjustified in such circumstances, we do not (and need not) go so far as to suggest that adoption of a good faith exception would have no effect at all on the presumed deterrability of Fourth Amendment violations. Perhaps it is tenable to support that, if police are responsive to the suppression sanction, then the more sweeping and stringent the use of the sanction, the more cautious they will be in cases in which there is any room for doubt about the legality of a proposed search or seizure, a point the Court made in United States v. Johnson, slip op. 23-24. But the mere fact that some deterrence may be postulated plainly cannot control the inquiry here. If it did, the Court's decisions imposing the "standing" requirement, for example, would be totally untenable; it is, after all, hardly disputable that a rule allowing any defendant to obtain suppression would be far more likely to deter than one excluding the fruits of reasonable, good faith searches. The question, in short, does not turn merely upon identification of some reasonable possibility of deterrence, but requires an evaluation of the substantiality of the anticipated deterrence. As the Court noted in Michigan v. Tucker, 417 U.S. 433, 447 (1974): The deterrent purpose of the exclusionary rule necessarily assumes that the police have engaged in willful, or at the very least negligent, conduct which has deprived the defendant of some right. By refusing to admit evidence gained as a result of such conduct, the courts hope to instill in those particular investigating officers, or in their future counterparts, a greater degree of care toward the rights of an accused. Where the official action was pursued in complete good faith, however, the deterrence rationale loses much of its force. Similarly, in Peltier, 422 U.S. at 542, the Court stated: If the purpose of the exclusionary rule is to deter unlawful police conduct then evidence obtained from a search should be suppressed only if it can be said that the law enforcement officer had knowledge, or may properly be charged with knowledge, that the search was unconstitutional under the Fourth Amendment. See also Janis, 428 U.S. at 458-459 n.35. 2. Experience teaches that Fourth Amendment violations vary greatly in their gravity and, we submit, in their amenability to deterrence. At one end of the spectrum, when officers have made Fourth Amendment intrusions under circumstances "so lacking in indicia of probable cause as to render official belief in its existence entirely unreasonable," or engaged in law enforcement activities that constitute "flagrantly abusive violation(s) of Fourth Amendment rights," "the deterrent value of the exclusionary rule is most likely to be effective." Brown v. Illinois, 422 U.S. 590, 610-611 (1975) (Powell, J., concurring). /6/ By contrast, when there is merely a "technical" violation of Fourth Amendment rights occasioned by actions that a reasonably well-trained police officer would not recognize as impermissible, "the deterrence rationale of the exclusionary rule does not obtain," and there is accordingly "no legitimate justification for depriving the prosecution of reliable and probative evidence." Id. at 611-612. In our view, if the exclusionary rule is to function tolerably in our society, it must take account of these differences. Thus, we endorse Justice White's opinion (Stone v. Powell, 428 U.S. at 538 (White, J., dissenting)) that the rule should be substantially modified so as to prevent its application in those many circumstances where the evidence at issue was seized by an officer acting in the good-faith belief that his conduct comported with existing law and having reasonable grounds for this belief. These are recurring situations; and recurringly evidence is excluded without any realistic expectation that its exclusion will contribute in the slightest to the purposes of the rule, even though the trial will be seriously affected or the indictment dismissed. /7/ This type of focused exception responsive to the policies of the exclusionary rule has been expressly adopted by the Fifth Circuit. United States v. Williams, 622 F.2d 830 (1980) (en banc), cert. denied, 449 U.S. 1127 (1981). There, a federal agent who had previously arrested Williams in Ohio for a narcotics violation encountered her in another state. The agent knew that a condition of Williams' release on bond pending appeal was that she remain in Ohio. Accordingly, the agent arrested Williams for violating this condition and, in ensuing searches incident to the arrest, seized heroin from Williams' possession. Sitting en banc, the Fifth Circuit held unanimously that the district court should not have suppressed the heroin. One majority of the court held that the federal agent had legal authority to arrest Williams because, by violating a condition of her bail release, she had committed the crime of contempt of court in the agent's presence (622 F.2d at 836-839). A different, overlapping majority of the court held that, irrespective of the validity of Williams' arrest, the heroin should not have been suppressed because the agent had acted in good faith in arresting and searching Williams, and could not reasonably be expected to have known that there was any serious doubt concerning his authority to make the arrest. Because the purpose of the exclusionary rule is to deter "willful or flagrant actions by police, not reasonable, good-faith ones" (622 F.2d at 840), the court concluded that it made no sense to suppress evidence in these circumstances, "unless we somehow wish to deter (police officers) from acting at all" (id. at 842). The court noted that its decision was fully consistent with this Court's cost-benefit approach to the exclusionary rule (id. at 842-843; citations omitted: Any slight deterrent effect of excluding fruits of good-faith arrests is even less than the small deterrence from suppressing the fruits of illegal police actions that are attenuated in effect, that are challenged in habeas corpus petitions on fourth amendment grounds, that are used in grand jury deliberations, or that are used for impeachment. Yet the Supreme Court has found that the deterrent effect of exclusion in the examples listed and others does not justify the societal harm incurred by suppressing relevant and incriminating evidence. * * * The good-faith exception that we explicitly recognize today is of a kind with these. /8/ 3. The facts in United States v. Williams, requiring the officer to make an on-the-spot legal decision concerning the scope of his arrest powers, an issue that had not been judicially resolved adversely to his action, vividly illustrate the need for modification of the exclusionary rule. Policemen are not trained legal technicians; nevertheless, they are expected to make quick decisions, often involving complicated legal and factual analyses, "in the course of the difficult and often dangerous business of law enforcement." Wright, Must the Criminal Go Free If the Constable Blunders?, 50 Tex. L. Rev. 736, 741 (1972). Thus, countless officers in the field must daily decide under rapidly-changing circumstances whether there exists the requisite probable cause to support an arrest or a search. In such cases, "(i)nadvertent errors of judgment" and "honest mistakes" will "inevitably occur given the pressures inherent in police work having to do with serious crimes." Bivens, 403 U.S. at 418 (Burger, C.J., dissenting). The uncertainties inherent in police work are exacerbated by a lack of coherent Fourth Amendment standards that are readily recognizable and predictably applied by officers in the field. Too often, courts leave police officers to resolve these difficult questions for themselves, see New York v. Belton, 453 U.S. 454, 470 (1981) (Brennan, J., dissenting), and then feel free to second-guess their entirely reasonable judgments. The result is that the courts have engendered a "state of uncertainty" that is "intolerable" to the officer on the beat. Coolidge v. New Hampshire, 403 U.S. at 490-491 (Harlan, J., concurring). /9/ Without the ability accurately to predict how courts will resolve Fourth Amendment questions, law enforcement officers will neither know the scope of their authority nor be sufficiently deterred from improper action to justify application of the exclusionary rule. See New York v. Belton, 453 U.S. at 459-460; see also LaFave, Improving Police Performance Through the Exclusionary Rule, 30 Mo. L. Rev. 391, 395 (1965). /10/ There is no basis for faulting an officer who has made a reasonable but incorrect assessment regarding the existence of reasonable suspicion or probable cause or the necessity of obtaining a warrant. Fourth Amendment adjudications inevitably leave "much room for disagreement among judges, each of whom is convinced that both he and his colleagues are reasonable men. Surely when this Court divides five to four on issues of probable cause, it is not tenable to conclude that the officer was at fault or acted unreasonably in making the arrest." Stone v. Powell, 428 U.S. at 540 (White, J., dissenting). /11/ Justice White went on to note (id. at 539-540): (E)xperience tells us that there will be those occasions where the trial or appellate court will disagree on the issue of probable cause, no matter how reasonable the grounds for arrest appeared to the officer and though reasonable men could easily differ on the question. It also happens that after the events at issue have occurred, the law may change, dramatically or ever so slightly, but in any event sufficiently to require the trial judge to hold that there was not probable cause to make the arrest and to seize the evidence offered by the prosecution. * * * In these situations, and perhaps many others, excluding the evidence will not further the ends of the exclusionary rule in any appreciable way; for it is painfully apparent that in each of them the officer is acting as a reasonable officer would and should act in similar circumstances. Excluding the evidence can in no way affect his future conduct unless it is to make him less willing to do his duty. /12/ Quite clearly, it is in these "grey, twilight area(s), where the law is difficult for courts to apply, let alone for the policeman on the beat to understand," that the exclusionary rule is least efficacious in deterring police misconduct. Schneckloth v. Bustamonte, 412 U.S. at 269 (Powell, J., concurring). /13/ 4. The good faith exception to the exclusionary rule that we advocate here is consistent with this Court's recognition of the ameliorating effects of police good faith in other Fourth Amendment contexts. For example, in Michigan v. DeFillippo, 443 U.S. 31 (1979), a police officer made an arrest in good-faith reliance on a municipal ordinance later declared to be unconstitutional. In an ensuing search incident to the arrest, the officer seized drugs from the defendant's person. In upholding the admissibility of the seized drugs, the Court stated (id. at 37-38): A prudent officer, in the course of determining whether (the defendant) had committed an offense under all the circumstances shown by this record, should not have been required to anticipate that a court would later hold the ordinance unconstitutional. * * * /14/ Similarly, in United States v. Caceres, 440 U.S. 741 (1979), Internal Revenue agents conducted a series of "consensual electronic surveillance" encounters with a targeted taxpayer. Although internal agency guidelines required prior authorization for such surveillance, the agents failed to obtain written authorization. Refusing to require suppression of the fruits of the unauthorized surveillance, the Court noted that "(t)he agency action, while later found to be in violation of the regulations, nonetheless reflected a reasonable, good-faith attempt to comply in a situation" in which monitoring was appropriate and would have been authorized had the request for authorization been received more promptly (id. at 757). So too, in Hill v. California, 401 U.S. 797 (1971), officers had probable cause to arrest Hill; however, the officers mistakenly arrested one Miller, who was present in Hill's apartment, and conducted a search incident to the arrest that disclosed evidence incriminating Hill. In upholding the validity of the seizure, the Court stated: "The upshot was that the officers in good faith believed Miller was Hill and arrested him. They were quite wrong as it turned out, and subjective good-faith belief would not in itself justify either the arrest or the subsequent search. But * * * the officers' mistake was understandable and the arrest a reasonable response to the situation facing them at the time" (401 U.S. at 803-804). Finally, in Franks v. Delaware, 438 U.S. 154 (1978), the Court limited the circumstances in which a defendant may challenge the truthfulness of allegations in a search warrant affadavit to those effectively involving official bad faith. Thus, as the Court made clear, "(t)here must be allegations of deliberate falsehood or of reckless disregard for the truth * * * . Allegations of negligence or innocent mistake are insufficient" (id. at 171). 5. Finally, the good faith exception to the exclusionary rule that we propose comports fully with the context in which the rule was first promulgated and then applied to the states. It has been noted that pre-Mapp cases frequently involved "arrogant or brazen police behavior." Schroeder, Deterring Fourth Amendment Violations: Alternatives to the Exclusionary Rule, 69 Geo. L.J. 1361, 1414-1415 (1981) (footnote omitted). As we observed at the outset (see page 9, supra), both Weeks and Mapp involved warrantless, exploratory searches through private papers and effects. So too, many of the early cases in which the exclusionary rule was first applied involved equally egregious misconduct. /15/ In keeping with this historical perspective, nothing in the modification we propose will prevent courts from excluding evidence obtained through intentional or clearly abusive police misconduct. But it makes no sense to apply a rule of suppression that was conceived in the context of palpably egregious police misconduct to the multitude of present-day cases in which law enforcement officers make reasonable, good-faith efforts to comply with the Constitution. Police resort to the preferred warrant procedure has markedly increased in the years since Mapp was decided (see 1 W. LaFave, Search and Seizure: A Treatise on the Fourth Amendment Section 1.2, at 26 (1978)), law enforcement officers have to a far greater extent become well-trained professionals, and the cases litigated most often probe the "grey, twilight areas" of Fourth Amendment law, rather than directly touching the core values of that constitutional protection. Against this background, neither the fundamental values of the Fourth Amendment nor the deterrent purpose of the exclusionary rule can be meaningfully advanced by the suppression of evidence when law enforcement officers attempt in good faith to navigate the intricate channels of Fourth Amendment law. Simply put, when law enforcement officers have acted in a manner far removed from the egregious type of conduct that the exclusionary rule was first designed to combat, their honest mistakes should not be met with the severe sanction of suppression. B. The Reasons For Applying the Exclusionary Rule Are Most Remote When Law Enforcement Officers Have Relied In Good Faith On A Judicially-Issued Search Warrant 1. Whether or not suppression may provide some deterrent against warrantless searches that police officers reasonably fail to recognize as improper, it is nothing short of irrational to expect any deterrent effects from the suppression of evidence obtained pursuant to judicially-issued search warrants. /16/ Rather, "(i)mposing an admittedly indirect 'sanction' on the police officer in that instance is nothing less than sophisticated nonsense" (Stone v. Powell, 428 U.S. at 498 (Burger, C.J., concurring)), because law enforcement officers will never be deterred from executing a search warrant that a judge has told them is valid. "Once the warrant issues, there is literally nothing more the policeman can do in seeking to comply with the law." Ibid. /17/ See United States v. Hill, 500 F.2d 315, 322 (5th Cir. 1974); Gifford v. State, 630 S.W.2d at 391; Richmond v. Commonwealth, 50 U.S.L.W. at 2162; cf. United States v. Ross, No. 80-2209 (June 1, 1982), slip op. 25 n.32 ("(A) warrant issued by a magistrate normally suffices to establish" that a law enforcement officer has "acted in good faith in conducting the search"); United States v. Alvarez-Porras, 643 F.2d 54, 65-66 (2d Cir.), cert. denied, 454 U.S. 839 (1981) (deterrent purpose of exclusionary rule is not served in circumstances that include the agents' good-faith attempt to comply with the warrant requirement). /18/ Quite clearly, neither the fundamental values of the Fourth Amendment nor the deterrent purpose of the exclusionary rule can be meaningfully advanced by the suppression of evidence in situations where a search warrant is invalidated because of a technical defect, e.g., United States v. Shorter, 600 F.2d 585 (6th Cir. 1979); Commonwealth v. Sheppard, 32 Crim. L. Rep. (BNA) 2157 (Dec. 1, 1982), /19/ because the issuing official, although authorized by statute to issue warrants, is found to lack the requisite degree of neutrality, see Coolidge v. New Hampshire, 403 U.S. 443 (1971), /20/ or because, as in the present case, a reasonable, good-faith presentation of information to a neutral judicial officer is later determined to fall short of probable cause, e.g., United States v. Karathanos, 531 F.2d 26, 35 (2d Cir.), cert. denied, 428 U.S. 910 (1976). Importantly, this Court has never articulated any rationale for applying the exclusionary rule to suppress evidence obtained pursuant to a search warrant; it has simply done so without discussing the policies to be served. The situation is thus remarkably similar to that presented in Stone v. Powell, in which the Court acknowledged that its prior decisions had not fully considered the extent to which the exclusionary rule should apply in federal habeas corpus proceedings (428 U.S. at 480-481 & n.15). Upon examination, of course, the Court concluded that the cost of permitting state prisoners to relitigate search and seizure issues outweighed any incremental deterrent effect that might flow from application of the exclusionary rule. Here, too, the Court is presented with its first real occasion to examine the policies of the exclusionary rule as they relate to evidence obtained pursuant to a warrant. As in Stone v. Powell, should that examination reveal the absence of sufficient justification for continuing to apply the exclusionary rule in such circumstances, the Court should not hesitate to modify the rule. 2. Application of the exclusionary rule to the fruits of judicially-warranted searches is not only irrational, but may well reduce incentives for police resort to the warrant procedure, which this Court has repeatedly held is the constitutionally preferred method for safeguarding individual privacy rights. United States v. United States District Court, 407 U.S. 297, 317 (1972); Terry v. Ohio, 392 U.S. 1, 20 (1968); United States v. Ventresca, 380 U.S. 102, 106-107 (1965); Johnson v. United States, 333 U.S. 10, 14 n.3 (1948); 2 W. LaFave, Search and Seizure: A Treatise on the Fourth Amendment Section 4.2, at 29 (1978). /21/ Thus, a good-faith exception to the exclusionary rule when a warrant has been obtained would provide a substantial incentive for law enforcement officers to utilize the preferred warrant procedure. See Brown v. Illinois, 422 U.S. at 611 & n.3 (Powell, J., concurring). Unlike instances in which the police have acted without judicial authorization and in which an exclusionary rule might, in limited circumstances, provide a deterrent to future misconduct, resort to the warrant procedure itself provides a substantial alternative barrier to unreasonable or otherwise defective searches and seizures. See Jones v. United States, 362 U.S. 257, 270-271 (1960); Johnson v. United States, 333 U.S. at 14; United States v. Lefkowitz, 285 U.S. 452, 464 (1932). For this reason, the Court has recognized that errors of judgment by a magistrate should not necessarily be treated as severely as Fourth Amendment violations by law enforcement officers acting without judicial supervision and approval. See United States v. Watson, 423 U.S. 411, 423 (1976); Spinelli v. United States, 393 U.S. 410, 419 (1969); United States v. Ventresca, 380 U.S. at 109; Aguilar v. Texas, 378 U.S. 108, 111 (1964); Jones v. United States, 362 U.S. at 270-271. As the Court explained in Aguilar, 378 U.S. at 111, quoting Jones, 362 U.S. at 271: (W)hen a search is based upon a magistrate's, rather than a police officer's, determination of probable cause, the reviewing courts will accept evidence of a less "judicially competent or persuasive character than would have justified an officer in acting on his own without a warrant," * * * and will sustain the judicial determination so long as "there was substantial basis for (the magistrate) to conclude that narcotics were probably present. . . . " A good-faith exception to the exclusionary rule in the case of evidence seized pursuant to a warrant would thus fully comport with the special status the Court has attached to warrants in the past. 3. Moreover, we submit that the exclusionary rule is an inherently inappropriate device for deterring Fourth Amendment violations that are the result of judicial miscalculation, rather than police misconduct. As the Court observed in Janis, 428 U.S. at 448, application of the exclusionary rule must be tied to the identity of those who are to be deterred and the nature of the conduct that is to be controlled. And, in the Fourth Amendment context, the purpose of the rule is to deter police miscalculation, not judicial errors. /22/ Accordingly, as was recognized by the Supreme Judicial Court of Massachusetts (Commonwealth v. Sheppard, 32 Crim. L. Rep. (BNA) at 2158): The exclusionary rule may not be well tailored to deterring judicial misconduct. If applied to judicial misconduct, the rule would be just as costly as it is when it is applied to police misconduct, but it may be ill-fitted to the job-created motivations of judges. As we have said, ideally a judge is impartial as to whether a particular piece of evidence is admitted or a particular defendant convicted. Hence, in the abstract, suppression of a particular piece of evidence may not be as effective a disincentive to a neutral judge as it would be to the police. It may be that a ruling by an appellate court that a search warrant was unconstitutional would be sufficient to deter similar conduct in the future by magistrates. We question, therefore, whether suppression of evidence is necessary as a deterrent in cases where the police conduct was entirely proper, the defendant was not prejudiced by the magistrate's error, and an appellate court clearly identifies the magistrate's error of law as a guide to future conduct. /23/ 4. We do not suggest that the exclusionary rule is never appropriate when a search has been conducted pursuant to a warrant, or that the mere issuance of a warrant wholly forecloses further inquiry into the existence of probable cause. Even when a warrant has been obtained, suppression of evidence may be justified if the factors relied on by the magistrate "were so lacking in indicia of probable cause as to render official belief in its existence entirely unreasonable," Brown v. Illinois, 422 U.S. at 610-611 (Powell, J., concurring), or if the warrant had been procured in bad faith or on the basis of material misrepresentations, see Franks v. Delaware, 438 U.S. 154 (1978). Application of the rule in such circumstances would be consistent with its historic underpinnings. But as Professor Amsterdam has written, "the rule is a needed, but grudingly (sic) taken, medicament; no more should be swallowed than is needed to combat the disease." Amsterdam, Search, Seizure, and Section 2255: A Comment, 112 U. Pa. L. Rev. 378, 389 (1964). Manifestly, the rare circumstances that might justify exclusion of the fruits of a judicially-warranted search are not present here, in view of the meticulous care taken by the police to ensure that their conduct at all times comported with constitutional requirements. First, rather than taking precipitous action based on the anonymous tip, the police independently investigated the allegations in the tip and sought to corroborate them through surveillance of Lance Gates. When their surveillance confirmed the accuracy of much of the information provided in the tip, the police did not act on their own initiative, but instead sought a warrant from a neutral judicial officer. /24/ Moreover, they provided the judicial officer with every bit of information they possessed that would assist him in making a reasoned, independent decision, including copies of the informant's letter and the report from the Illinois Secretary of State (see Pet. App 4b, 10b). And they executed the warrant properly and in the good-faith belief that it was valid. In turn, the judge issuing the warrant clearly had at least "reasonable cause to believe there was reasonable cause." H. Friendly, Benchmarks 261 (1967). In these circumstances, it would advance no Fourth Amendment policy to suppress the seized evidence. C. In Light Of The Exclusionary Rule's Inability To Fulfill Its Deterrent Purpose When Applied To Honest Mistakes, Its Costs are Higher Than Our System Of Criminal Justice Can Afford Many of the costs of the exclusionary rule have been alluded to in previous sections of this brief. Nevertheless, in completing the cost-benefit analysis that we commend to the Court, it is appropriate to recapitulate briefly the most obvious costs and to elaborate more fully on some of the less evident ones. First, the exclusionary rule excludes from consideration at trail the very evidence that is most relevant and trustworthy. /25/ The rule thus subverts the courts' paramount truthfinding function. See, e.g., Stone v. Powell, 428 U.S. at 489; id. at 499-500 (Burger, C.J., concurring); Janis, 428 U.S. at 448-449. Second, the exclusionary rule benefits only those who are unquestionably guilty. In the now-famous words of Justice Cardozo, particularly apt to consideration of a good-faith exception, the rule allows "(t)he criminal * * * to go free because the constable has blundered." People v. Defore, 242 N.Y. 13, 21, 150 N.E. 585, 587, cert. denied, 270 U.S. 657 (1926). The rule does nothing, however, to repair injury to innocent victims of unreasonable searches. Proponents of the exclusionary rule have argued that only a very small number of guilty defendants actually go free because of it, and that this is a small price to pay to safeguard the Fourth Amendment rights of all citizens. /26/ In addition to the fact that the freeing of even one guilty defendant by virtue of an irrational rule may exact a greater cost than society should be expected to bear (see pages 50-52, infra), this argument disregards evidence that tends to demonstrate very real costs, in numerical terms, of the rule's operation. For the proposition that the exclusionary rule actually affects relatively few defendants, the rule's proponents generally point to a 1979 study by the General Accounting Office, which concluded that of all cases declined for prosecution by United States Attorneys, Fourth Amendment search and seizure problems were the primary reason for declination in only 0.4% of the total. Comptroller General of the United States, Rep. No. GGD-79-45, Impact of the Exclusionary Rule on Federal Criminal Prosecutions 14 (1979) (hereinafter cited as "GAO Report"). Emphasis on the relatively low declination rate, however, ignores other significant findings of the GAO study. /27/ For example, the GAO study noted the dramatic effect that a successful suppression motion is likely to have on the outcome of individual cases. In more than 84% of the cases in which a suppression motion had been denied, a conviction was obtained. The conviction rate dropped dramatically, however, to about 50%, whenever a suppression motion had been granted in whole or in part. Id. at 13. Although the GAO study did not attempt to explain the reasons for these differences, it is obvious, as the GAO Report acknowledged (ibid.), that a definite relationship exists between the suppression of evidence and the prosecution's ability to obtain a conviction. Equally important, the GAO study has been criticized for its failure to break down its results by the nature of the criminal charges. Certain types of crimes, particularly those involving drugs or weapons, are much more likely than others to present search and seizure issues. Oaks, supra, 37 U. Chi. L. Rev. at 681-683. The GAO study, however, "simply analyzed aggregate data for a wide variety of federal felony arrests" in arriving at its conclusion that the exclusionary rule has little apparent impact. National Institute of Justice, The Effects of the Exclusionary Rule: A Study in California 1 (Dec. 1982) (hereinafter cited as "NIJ Report"). Significantly, "(m) ost of the federal caseload at the time the (GAO) study was conducted was composed of such white collar crimes as embezzlement, fraud and forgery. Search and seizure issues are seldom raised in these cases." NIJ Report 7. /28/ In an attempt to provide more comprehensive data, the NIJ Report undertook a statewide study of all felony arrests in Califormia during the years 1976-1979, and then broke down its results by type of crime. The study's findings were significant. In contrast to the GAO study, the NIJ study "found a major impact of the exclusionary rule on state prosecutions" and further found that the impact was most pronounced in narcotics cases. NIJ Report 2. Looking at statewide felony arrests generally, NIJ found that 4.8% of the more than 4,000 felony cases declined for prosecution were rejected because of search and seizure problems. /29/ NIJ Report 1. This is 12 times the 0.4% declination rate reported by the GAO study. Moreover, the NIJ study found that the effect of the exclusionary rule in drug cases is truly substantial. Prosecutors rejected approximately 30% of all felony drug arrests because of search and seizure problems. NIJ Report 2. /30/ The NIJ study also provides important new data about the exclusionary rule's effect on society by examining the prior and subsequent arrest histories of defendants whose cases were dismissed. The study concluded (NIJ Report 2): For most defendants, the arrest that ended in release because of the exclusionary rule was only a single incident in a longer criminal career. About half of those freed were rearrested during the (two-year) follow-up period; they averaged approximately three rearrests each. * * * * To a substantial degree, individuals released because of search and seizure problems were those with serious criminal records who appeared to continue to be involved in crime after their release. The felony rearrests included many drug crimes, but the majority were for crimes against persons or property, or for other felony offenses. /31/ Given these findings, it simply cannot be denied that the exclusionary rule contributes significantly to the Nation's crime problem. /32/ But even if the numerical impact of the exclusionary rule were to be discounted, the rule exacts an exceedingly high societal cost. The Court has noted that the exclusionary rule may well serve to lessen public respect for the judicial system. "Thus, although the rule is sought to deter unlawful police activity in part through the nurturing of respect for Fourth Amendment values, if applied indiscriminately it may well have the opposite effect of generating disrespect for the law and administration of justice." Stone v. Powell, 428 U.S. at 490-491. Moreover, indiscriminate application of the exclusionary rule may foster a public perception that the courts are simply unaware of reality. See Bivens, 403 U.S. at 415 (Burger, C.J., dissenting) (deterrent rationale is "hardly more than a wistful dream"). /33/ In part, this problem of public perception arises because the exclusionary rule, as currently applied, lacks the vital ingredient of proportionality. /34/ As the Chief Justice observed in his concurrence in Stone v. Powell, 428 U.S. at 490: "The disparity in particular cases between the error committed by the police officer and the windfall afforded a guilty defendant by application of the rule is contrary to the idea of proportionality that is essential to the concept of justice." /35/ This cost of the exclusionary rule is particularly evident in a case such as the present one, where it cannot seriously be urged that the police engaged in any misconduct. See pages 44-45, supra. On the other hand, there can be little doubt that the suppressed evidence, if admitted, would conclusively establish the respondent's guilt. The chilling effect on legitimate police activities is another less visible but equally important cost specifically associated with suppression of evidence garnered in good faith violations of the Fourth Amendment. As the circumstances surrounding a particular proposed course of action bring it closer to the indistinct line often separating lawful from unlawful searches or seizures, a relentless application of the exclusionary rule is increasingly likely (accepting arguendo the premise of deterrence on which the rule depends) to deter the former rather than the latter, since almost by definition this class of situations is as likely to involve legal as illegal police activity. To the extent the rule operates to discourage the police from reasonable and proper investigative actions, it carries with it the truly deplorable consequence of unreasonably preventing the solution and, worse yet, prevention of crime. Once application of the rule approaches the point at which it is as likely to chill legitimate police action as to discourage marginally improper action, powerful justifications indeed are needed to justify such results. /36/ Still another cost of the exclusionary rule is its failure to provide any remedy for the innocent victims of unlawful searches and seizures. Even for the criminal defendant, the primary effect of the rule's application -- aiding him to secure an acquittal even though he is guilty -- does not itself repair the breach of privacy that the Fourth Amendment protects. See page 13, supra. And the exclusionary rule is, of course, an entirely meaningless "remedy" when the victim of the unlawful search is never accused of a crime. See Bivens, 403 U.S. at 410 ("(f)or people in Bivens' shoes, it is damages or nothing"); id. at 415-416, 417-418 (Burger, C.J., dissenting). A further cost of the exclusionary rule, often paid insufficient attention, is the burden it places on the judicial system. One-third of federal defendants going to trial file Fourth Amendment suppression motions, and 70% to 90% of these involve formal hearings. GAO Report 10. Although most of these motions are denied (ibid.), the effect on judicial and prosecutorial resources is the same as if the motions were meritorious. Significantly, the result of this diversion of resources from criminal trials to pre-trial motions may have its harshest impact on innocent defendants. See United States v. Ross, 655 F.2d at 1205-1206 (Wilkey, J., dissenting): To understand how the innocent defendant is victimized by the diversion of scarce resources from criminal trials to police discipline, it is necessary briefly to consider how our criminal justice system now operates in fact, if not in theory. * * * (It) ensures that more due process will be required than the system can afford to pay for. As a result, trials have now been priced too high to be held in most circumstances * * * . Instead, we have come increasingly to rely on an informal system of negotiated settlements in the form of plea bargained arrangements between prosecutor and defendant. The results are woeful. Criminals guilty of grievous offenses routinely are permitted to escape with convictions for crimes far less serious carrying only wristslapping penalties. Meanwhile innocent defendants who might well have been vindicated at trial are coerced into settling for a conviction on a lesser charge * * * . It is against this background that we must measure the diversion of energy, talent and dollars from the central task of fairly determining the guilt and innocence of defendants into the work of adjudicating whether the police have blundered. * * * That function should be performed elsewhere and by others. The exclusionary remedy thus literally buys what little in the way of Fourth Amendment protection it affords at the cost of more trials for criminal defendants. Even if the rule did a fair job of promoting Fourth Amendment values, this would be at best a questionable bargain. /37/ Finally, the exclusionary rule in the long run threatens the very Fourth Amendment values it is intended to safeguard. "If one were diabolically to attempt to invent a rule sure slowly to undermine the substantive reach of the Fourth Amendment, it would be hard to do better than the exclusionary rule." United States v. Ross, 655 F.2d at 1206 (Wilkey, J., dissenting). This is because of the obvious reluctance of judges to condemn questionable practices under the Fourth Amendment when they know that the result of their decision will be the freeing of a guilty defendant. The Court has noted the same effect in considering the permissibility of a retrial under the Double Jeopardy Clause (United States v. Tateo, 377 U.S. 463, 466 (1964): Corresponding to the right of an accused to be given a fair trial is the societal interest in punishing one whose guilt is clear after he has obtained such a trial. It would be a high price indeed for society to pay were every accused granted immunity from punishment because of any defect sufficient to constitute reversible error in the proceedings leading to conviction. From the standpoint of a defendant, it is at least doubtful that appellate courts would be as zealous as they now are in protecting against the effects of improprieties at the trial or pretrial stage if they knew that reversal of a conviction would put the accused irrevocably beyond the reach of further prosecution. In reality, therefore, the practice of retrial serves defendants' rights as well as society's interest. Similar concerns operate in the context of the exclusionary rule. In addition, public support for the values served by the Fourth Amendment can too easily be undermined by a general perception that Fourth Amendment jurisprudence is bringing about the seemingly unjustified release into society of dangerous criminals. Thus, the rule cannot help but threaten the substantive safeguards of the Fourth Amendment. D. The Objections To A Good-Faith Exception To The Exclusionary Rule Are Insufficient To Overcome The Need For Modification We think it evident that the foregoing cost-benefit analysis of the exclusionary rule demonstrates the need for a properly designed good-faith exception to the rule. Although many of the practical details concerning the application of such an exception are best left to future cases and initial resolution by lower courts, cf. United States v. Williams, 622 F.2d at 847; United States v. Nolan, 530 F. Supp. at 399, we shall undertake briefly, and in general terms, to respond to some of the most commonly-voiced objections to our proposal. 1. Critics of a good-faith exception to the exclusionary rule invariably argue that it would "put() a premium on 'police ignorance.' " /38/This is a palpable strawman. As the Fifth Circuit explained in United States v. Williams, 622 F.2d at 841 n.4a, the test for applying the exception is essentially an objective one: We emphasize that the belief, in addition to being held in subjective good faith, must be grounded in an objective reasonableness. It must therefore be based upon articulable premises sufficient to cause a reasonable, and reasonably trained, officer to believe that he was acting lawfully. Thus, a series of broadcast breakins and searches carried out by a constable -- no matter how pure in heart -- who had never heard of the fourth amendment could never qualify. See also United States v. Nolan, 530 F.Supp. at 399; People v. Adams, 53 N.Y.2d at 9-10, 422 N.E.2d at 541; Carrington, Good Faith Mistakes and the Exclusionary Rule, 1 Crim. Just. Ethics 35, 38-39 (1982); Schroeder, supra, 69 Geo. L.J. at 1420; Ball, Good Faith and the Fourth Amendment: The "Reasonable" Exception to the Exclusionary Rule, 69 J. Crim. L. & Criminology 635, 655 (1978); cf. Scott v. United States, 436 U.S. 128, 137-138 (1978). Thus, a modification of the exclusionary rule that focuses on the objective reasonableness of an officer's actions will not foster official disregard for the law. Because such an objective standard requires individual officers to have a reasonable knowledge of what the law prohibits, see United States v. Peltier, 422 U.S. at 542; United States v. Ajlouny, 629 F.2d at 841; United States v. Noaln, 530 F. Supp. at 399, adoption of a good-faith exception may actually enhance, but in any event certainly will not discourage, efforts to educate police officers about the extant principles of law. To avoid the risk of suppression through unreasonable ignorance, police departments can be expected (assuming validity in the hypothesis of deterrence by which the rule is justified in the first place) to ensure that individual officers are reasonably well-trained, especially as to the extent to which a police department takes seriously its duty of providing training and guidance to officers in the field might well be considered in determining whether the exclusionary rule should be invoked. See Kaplan, supra, 26 Stan. L. Rev. at 1050-1051. 2. Because the focus of the inquiry will be objective reasonableness, rather than an officer's subjective intent, the good-faith exception we propose is not likely to burden the courts unduly. Generally, it will be unnecessary for courts to engage in unwieldy and awkward inquiries into the subjective intent of arresting or searching officers. /39/ Instead, a good-faith exception would require only an objective assessment of the officer's conduct in light of the factual circumstances of a particular case and the extent to which the governing legal principles have been predictably articulated. It will, therefore, merely require courts to make determinations of a kind that are not materially different from those they presently make in ruling upon suppression motions. /40/ 3. It is sometimes suggested that the exclusionary rule is needed to provide Fourth Amendment cases for the courts to adjudicate. See, e.g., Goodpaster, An Essay on Ending the Exclusionary Rule, 33 Hastings L. J. 1065, 1074 (1982); Geller, Enforcing the Fourth Amendment: The Exclusionary Rule and its Alternatives, 1975 Wash. U.L.Q. 621, 654-656; Oaks, supra, 37 U. Chi. L. Rev. at 756. "The risk (in modifying the exclusionary rule) is that our constitutional rights will atrophy." Geller, supra, at 655 (footnote omitted). This presumed risk should be placed in proper perspective. Assuming, arguendo, that adoption of a good-faith exception to the exclusionary rule would substantially reduce the incentive for defendants to litigate substantive Fourth Amendment questions, the Court should bear in mind that the lost decisionmaking opportunities will be confined to the "grey, twilight area(s)" of Fourth Amendment law where the constitutional violation, if any, is minimal. In these areas at least, it would seem that our society would reap greater benefits from a more rational application of the exclusionary rule than from continued judicial resolution of every Fourth Amendment question that inventive lawyers can devise. Just as there is a point of diminishing returns in the application of the exclusionary rule, /41/ so too there is a point at which decisions of only marginal constitutional significance may be overpriced. In any event, we are extremely skeptical about the validity of any assumption that defendants will lose their incentive to litigate substantive Fourth Amendment questions if confronted with a good-faith exception to the exclusionary rule. The overwhelming lack of success of most suppression motions (see page 53, supra) does not seem to have had any effect on the number of such motions filed. Practical experience tells us that criminal defendants commonly assert suppression claims with little regard for their ultimate chances of success -- in part, no doubt, because of the magnitude of the benefit to them if "lightning" should strike. While adoption of a good-faith exception will tend to discourage presentation of substantively insubstantial Fourth Amendment suppression motions, it thus seems highly improbable that litigation of colorable Fourth Amendment issues will "atrophy" to any significant degree. Although the number of cases may not materially decline, there would be an important easing of the judicial workload because it would no longer be necessary for courts to decide every conceivable question of Fourth Amendment law. The application of established law to the circumstances of a particular search and seizure to determine good faith will generally be an easier undertaking than resolution of the underlying legal question and should thus result in important advances for the cause of judicial economy. On the other hand, we see no jurisprudential impediment to a court's undertaking to decide important, recurrent, and unsettled substantive Fourth Amendment questions even when the good-faith exception may control the outcome of the particular case. Instead, we view the issue of whether to decide the substantive question first or to dispose of a case strictly on the basis of good faith as one best committed to judicial discretion. In nonrecurring, fact-bound situations, a court might well conclude that little purpose is served by unnecessarily adjudicating the Fourth Amendment question. On the other hand, significant legal issues or particularly problematic factual situations of concern to a court could still be considered. /42/ This would be comparable to the approach now employed by the Court in applying the harmless error doctrine. In some cases, the Court exercises its discretion to decide the merits of a claim even though the error was harmless, while in others it resolves the case solely by reliance on the harmless error doctrine. Compare, e.g., Milton v. Wainwright, 407 U.S. 371, 372 (1972) (Court declines to decide whether admission of confession was constitutional violation because error, if any, was harmless beyond a reasonable doubt), with Coleman v. Alabama, 399 U.S. 1 (1970) (Court holds defendants constitutionally entitled to counsel at preliminary hearing, but remands to state court for determination whether denial of counsel was harmless error); /43/ see also United States v. Blackwell, No. 82-1261 (D.C. Cir. Dec. 10, 1982), slip op. 31 n.22 (court explains reasons for deciding constitutional question before determining there was no "plain error"). Accordingly, the fear that Fourth Amendment law will become "frozen" in its current state seems groundless. 4. Finally, both supporters and critics of the exclusionary rule have expressed reluctance about modifying it in the absence of an effective alternative. See, e.g., Bivens, 403 U.S. at 415, 420-421 (Burger, C. J., dissenting); Goodpaster, supra, 33 Hastings L. J. at 1100; Geller, supra, 1975 Wash. U.L.Q. at 688. If the exclusionary rule were actually capable of deterring good-faith police mistakes, this concern would have some force. We have already noted, however, as has the Court (see pages 20-23, supra), that there is at most an impressionistic basis for the assumption that the exclusionary rule in fact deters police misconduct. More importantly, in many of the cases to which a good-faith exception would apply, such as the instant one, there is no misconduct to deter. Under these circumstances, it simply makes no sense to hold on to a demonstrably costly "remedy" that is incapable of achieving its stated purpose. In our submission, the exclusionary rule must be evaluated on its own merits; if it fails to accomplish its objective, it should be appropriately modified, irrespective of the efficacy of the alternatives that might be substituted. In any event, a number of alternatives have been suggested. See, e.g., Wilkey, supra, 1 Crim. Just. Ethics at 24-26 (suggests executive branch disciplinary boards, civil tort remedies, or "mini-trials" for offending officers following the main criminal trial); Goodpaster, supra, 33 Hastings L. J. at 1100-1107 (recommends administrative agency regulation of police conduct). Whether any of these alternatives will be effective cannot be known until they are tested; what should be obvious, however, is that the alternatives cannot possibly be any less effective than the exclusionary rule in its current form for cases like the present one. Moreover, as has been noted by others, the continued existence of the exclusionary rule may itself actually inhibit experimentation with different approaches by the political branches of government. See Stone v. Powell, 428 U.S. at 491 (Burger, C. J., concurring); United States v. Ross, 655 F.2d at 1208 (Wilkey, J., dissenting); Schroeder, supra, 69 Geo. L. J. at 1385. Accordingly, we submit that the presence or absence of immediately available effective alternatives is simply not a controlling consideration in deciding whether the current role requires the kind of modification that we propose. CONCLUSION The judgment of the Illinois Supreme Court should be reversed. Respectfully submitted. REX E. LEE Solicitor General D. LOWELL JENSEN Assistant Attorney General ANDREW L. FREY Deputy Solicitor General KATHRYN A. OBERLY Assistant to the Solicitor General GEOFFREY S. STEWART ROBERT J. ERICKSON Attorneys JANUARY 1983 /1/ As one commentator put it, "the exclusionary rule does not 'look' like a constitutional doctrine. * * * (It) is merely one arbitrary point on a continuum between deterrence of illegal police activity and conviction of guilty persons." Kaplan, The Limits of the Exclusionary Rule, 26 Stan. L. Rev. 1027, 1030 (1974). /2/ These decisions would not be sustainable if the imperative of judicial integrity were a substantial independent basis for the exclusion of illegally obtained evidence, because the impact on judicial integrity of such use does not depend in the least upon whether the particular defendant's rights were infringed in procuring the tainted evidence. /3/ To the extent that United States v. Johnson, No. 80-1608 (June 21, 1982), may be read as a departure from these cases, we suggest that it reflects only the Court's concern with according fundamental fairness for persons similarly situated rather than any general retreat from the balancing analysis that the Court has consistently employed in the context of the exclusionary rule. /4/ Using the same reasoning, lower federal courts have placed similar limitations on the application of the exclusionary rule. See, e.g., Donovan V. Federal Clearing Die Casting Co., No. 82-1174 (7th Cir. Dec. 9, 1982) (exclusionary rule inapplicable to evidence seized by Occupational Safety and Health Administration pursuant to subsequently-invalidated search warrant); Tirado V. Commissioner, No. 81-4136 (2d Cir. Sept. 7, 1982) (evidence unlawfully seized by federal narcotics agents admissible in a federal civil tax proceeding; unlikely that narcotics agents would be deterred by prospect that illegally seized evidence might be unavailable in a future tax proceeding); United States V. Lee, 540 F.2d 1205, 1211 (4th Cir.), cert. denied, 429 U.S. 894 (1976) (exclusionary rule inapplicable to sentencing proceedings); United States V. Schipani, 435 F.2d 26, 28 (2d Cir. 1970), cert. denied, 401 U.S. 983 (1971) (same); United States V. Winsett, 518 F.2d 51, 53-55 (9th Cir. 1975) (exclusionary rule inapplicable at parole revocation hearings); United States V. Hill, 447 F.2d 817, 818-819 (7th Cir. 1971) (same); United States ex rel. Sperling V. Fitzpatrick, 426 F.2d 1161, 1163-1164 (2d Cir. 1970) (same). /5/ Justice Murphy's study consisted of 26 replies to a questionnaire he himself sent to the police chiefs of 38 large cities. Only those replies "of any significance" were discussed in the text of his dissenting opinion (338 U.S. at 44 n.5). However commendable Justice Murphy's attempt to gather empirical evidence may have been, he himself recognized the need for more comprehensive research (ibid.). /6/ "(T)he object of deterrence would be sufficiently achieved if the police were denied the fruit of activity intentionally or flagrantly illegal -- where there was no reasonable cause to believe there was reasonable cause." H. Friendly, Benchmarks 261 (1967). See also Wright, Must the Criminal Go Free If the Constable Blunders?, 50 Tex. L. Rev. 736, 744-745 (1972). In accord with that sentiment, the ALI's Model Code of Pre-Arraignment Procedure Section SS290.2(2) (1975), provides that "(a) motion to suppress evidence * * * shall be granted only if * * * the violation upon which it is based was substantial * * *." In turn, the substantiality of a violation is to be determined from a consideration of "all the circumstances" of a case (id. at Section SS290.2(4)), except in those situations where a violation is "gross, wilful and prejudicial to the accused" or "appears to be part of the practice of the law enforcement agency" (id. at Section SS290.2(3)). As one commentator has stated, "the purpose of the test is to invite courts to reconsider the need for exclusion where the fourth amendment violation is relatively minor and is neither willful nor reflective of agency policy or general indifference to individuals' rights." Schroeder, Deterring Fourth Amendment Violations: Alternatives to the Exclusionary Rule, 69 Geo. L. J. 1361, 1423 (1981). /7/ We need not here essay a precise delineation of the contours of an appropriate "good-faith" exception. At a minimum, it would cover the situation in which it can fairly be concluded that no reasonable police officer could have appreciated that his conduct was barred by the Fourth Amendment. At its broadest, it would exclude from its embrace only those "flagrantly abusive" violations (Brown V. Illinois, 422 U.S. at 610 (Powell, J., concurring)) that any minimally trained police officer should have known to be prohibited. This case does not call upon the Court to refine the concept very far because, as we discuss more fully hereafter, even the most modest formulation of the exception would amply suffice to allow introduction of the evidence discovered in execution of the search warrant here. We do stress, however, that any formulation of the principle should rest upon an objective standard for evaluating "good-faith," and that arguments that adoption of such an exception would place a premium upon police ignorance of the law are wholly erroneous and misplaced (see pages 57-59 & n.39, infra). /8/ The Fifth Circuit is not the only court to have adopted a good faith exception to the exclusionary rule. See United States V. Ajlouny, 629 F.2d 830, 840-841 (2d Cir. 1980), cert. denied, 449 U.S. 1111 (1981) (even if warrantless national security wiretap was unlawful, suppression not required where agents acted in good faith and could not be charged with knowledge that their conduct was improper); United States V. Nolan, 530 F. Supp. 386, 396-399 (W.D. Pa. 1981) (suppression not required for what was, at most, a technical, good faith violation of the knock-and-announce rule); United States V. Wilson, 528 F. Supp. 1129, 1132 (S.D. Fla. 1982) (even if arrest effectuated outside of officers' territorial jurisdiction was not a lawful citizen's arrest, good faith exception bars suppression of marijuana); Gifford V. State, 630 S.W.2d 387, 391 (Tex. Ct. App. 1982) (suppression not required where officers relied in good faith on a search warrant later found to be technically defective); Richmond V. Commonwealth, 50 U.S.L.W. 2162 (Ky. Ct. App. 1981) (same); People V. Adams, 53 N.Y.2d 1, 9-10, 422 N.E.2d 537, 541 (1981) (suppression not required where agent relied in reasonable good faith on purported authority of accused's girlfriend to consent to a search of his apartment); cf. cases cited at page 18 note 4, supra. The Supreme Judicial Court of Massachusetts recently declined to adopt such an exception, but only because it felt constrained to wait for this Court to do so first. Commonwealth V. Sheppard, 32 Crim. L. Rep. (BNA) 2157 (Dec. 1, 1982). The dissent, noting that the only defect in the search warrant was the failure to attach or incorporate by reference the officers' supporting affidavit, observed that "for want of a staple, highly probative evidence is lost. Such dedication to rigid formality is commanded neither by the Constitution nor by logic." Id. at 2158. A number of legal commentators have joined the Fifth Circuit and other courts following its lead in noting the absence of any meaningful deterrent effect when police officers have acted in the reasonable, good faith belief that their conduct was lawful. See, e.g., Carrington, Good Faith Mistakes and the Exclusionary Rule, 1 Crim. Just. Ethics 35, 37-38 (1982); Schroeder, Deterring Fourth Amendment Violations: Alternatives to the Exclusionary Rule, 69 Geo. L. J. 1361, 1380 (1981); Ball, Good Faith and the Fourth Amendment: The "Reasonable" Exception to the Exclusionary Rule, 69 J. Crim. L. & Criminology 635, 650 (1978); Kaplan, The Limits of the Exclusionary Rule, 26 Stan. L. Rev. 1027, 1044 (1974). /9/ As Justice Frankfurter once remarked, "the course of true law pertaining to searches and seizures * * * has not -- to put it mildly -- run smooth." Chapman V. United States, 365 U.S. 610, 618 (1961) (Frankfurther, J., concurring). See also Cady V. Dombrowski, 413 U.S. 433, 440 (1973) ("this branch of the law is something less than a seamless web"). Legal commentators have agreed with these observations. See, e.g., Amsterdam, Perspectives on the Fourth Amendment, 58 Minn. L. Rev. 349 (1974) ("For clarity and consistency, the law of the fourth amendment is not the Supreme Court's most successful product"); Kaplan, The Limits of the Exclusionary Rule, 26 Stan. L. Rev. 1027, 1033 (1974) (Fourth Amendment law "is so complicated and abstruse that the police often honestly and reasonably cannot determine in advance" how it will be applied); Goodpaster, An Essay on Ending the Exclusionary Rule, 33 Hastings L. J. 1065, 1092 (1982) (Fourth Amendment law marked by "sophisticated, complicated, and confusing decisions"). /10/ As Professor LaFave has noted, "(t)he threat of evidence exclusion can have little impact unless decision-making officers have some basis for determining what conduct will bring about exclusion" (id. at 396). /11/ And, of course, the instances are legion in which lower courts have erroneously condemned officers' actions as violative of the Fourth Amendment. See, e.g., New York V. Belton, 453 U.S. 454 (1981); United States V. Cortez, 449 U.S. 411 (1981); Colorado V. Bannister, 449 U.S. 1 (1980); United States V. Ramsey, 431 U.S. 606 (1977); United States V. Martinez-Fuerte, 428 U.S. 543 (1976); United States V. Watson, 423 U.S. 411 (1976); Texas V. White, 423 U.S. 67 (1975). Even as this is written, the Court has at least 11 cases (see pages 54-55 note 37, infra), including this one, in which it has undertaken to review holdings of lower courts that may well have confused or misunderstood the dictates of the Fourth Amendment in holding a search or seizure unlawful. /12/ Lower court judges have made the same point. For example, in Government of the Virgin Islands V. Rasool, 657 F.2d 582, 595 (3d Cir. 1981) (Adams, J., concurring), Judge Adams observed: (I)t is not realistic to expect the exclusionary rule to deter misconduct on the part of police officers. Often there is no misconduct to deter or punish -- the officer has simply acted reasonably in a pressured situation and is later told he guessed wrong about how Supreme Court precedents might be interpreted to apply in fine-line situations. In a similar vein, Judge Wilkey has noted (United States V. Ross, 655 F.2d 1159, 1204 (D.C. Cir. 1981) (en banc) (Wilkey, J., dissenting), rev'd, No. 80-2209 (June 1, 1982)): (T)oo many prosecutions * * * have gone awry, not as a result of intentional police misconduct, and certainly not because of any doubt about the guilt of the criminal, but simply because a court, with the benefit of time to reflect and of hindsight, concludes that an officer acting under pressure in the field, maybe under fear for his own life, failed properly to apply the often confused and confusing standards of conduct set out by courts interpreting the Constitution. Judge Wilkey also observed that in cases in which the law is not settled, courts "would have to impute to (police officers) nearly supernatural powers to see the future before we could charge (them) with knowledge that (their) conduct was unconstitutional" (id. at 1181). /13/ If concrete examples of the problem are necessary, one need only look to the Court's decisions in New York V. Belton, 453 U.S. 454 (1981), and Robbins V. California, 453 U.S. 420 (1981). The facts of the cases were remarkably similar. In both cases, police officers lawfully stopped a car, smelled burnt marijuana, discovered marijuana in the passenger compartment of the car, and lawfully arrested the occupants. Thereafter, in Robbins, the officer found two packages wrapped in green opaque paper in the recessed rear compartment of the car, opened them without a warrant, and found 30 pounds of marijuana. In Belton, the officer found a jacket in the passenger compartment, unzipped the pocket without a warrant, and found a quantity of cocaine. When the Court decided these cases, three Justices opined that both searches were legal; three Justices opined that they were both illegal; and three Justices controlled the ultimate decision that the search in Robbins was illegal and that in Belton legal. It may come as small consolation to the officer who made the search in Robbins that only a year later the decision was overruled in United States V. Ross, No. 80-2209 (June 1, 1982). /14/ The Court recognized (443 U.S. at 38 n.3): The purpose of the exclusionary rule is to deter unlawful police action. No conceivable purpose of deterrence would be served by suppressing evidence which, at the time it was found on the person of the (defendant), was the product of a lawful arrest and a lawful search. To deter police from enforcing a presumptively valid statute was never remotely in the contemplation of even the most zealous advocate of the exclusionary rule. /15/ See, e.g., Silverthorne Lumber Co. V. United States, 251 U.S. 385, 390-391 (1920) (prosecutor conceded "outrageous" conduct based on a warrantless documents search conducted "without a shadow of authority"); Gouled V. United States, 255 U.S. 298 (1921) (surreptitious document search); Agnello V. United States, 269 U.S. 20 (1925) (warrantless search of home as incident to an arrest that occurred blocks away); Go-Bart Importing Co. V. United States, 282 U.S. 344 (1931) (warrantless, exploratory search of documents); United States V. Jeffers, 342 U.S. 48, 52 (1951) (warrantless search of hotel room conducted "surreptitiously and by means denounced as criminal"). /16/ Professor Kaplan has noted that "application of the exclusionary rule is most clearly a windfall to the criminal" where a warrant is obtained that is later found to be defective, since it is "(i)n these situations (that) it is probable that the criminal would have been caught" even if all Fourth Amendment requirements had been met. See Kaplan, supra, 26 Stan. L. Rev. 1027, 1038 (1974). /17/ As Professor Levy has noted (L. Levy, Against the Law: The Nixon Court and Criminal Justice 81 (1974)): (T)o penalize the police by holding that a magistrate had not scrutinized the facts with enough independence is comparable to penalizing a prosecutor by holding that the police obtained the evidence illegally. The sanction of the law strikes the wrong party when the police have obtained a warrant. /18/ See also Schroeder, Deterring Fourth Amendment Violations: Alternatives to the Exclusionary Rule, 69 Geo. L.J. 1361, 1418-1419 (1981): A search conducted in accordance with the terms of the warrant necessarily involves good faith * * *. When the police have dutifully applied to a judge or a magistrate for a search warrant, and have executed the warrant in strict conformity with its terms, exclusion of the evidence thus obtained can have no possible deterrent effect on future police conduct. Accord, P. Johnson, New Approaches to Enforcing the Fourth Amendment 8-9 (Working Paper Sept. 1978), quoted in 1 W. LaFave, Search and Seizure: A Treatise on the Fourth Amendment Section 1.2, at 3 (Supp. 1982). /19/ In Shorter, suppression was ordered because, despite a clear demonstration of probable cause, the magistrate failed to administer an oath to the affiant "immediately" at the beginning of his telephonic application for a search warrant, as required by Rule 41(c)(2)(D), Fed. R. Crim. P. In Shephard, the state court reluctantly ordered suppression because the police officers' supporting affidavit was neither attached to nor incorporated by reference into the search warrant. /20/ Concurring in Coolidge, Justice Harlan noted that nothing in the unlawful conduct in that case touched on "core" Fourth Amendment values (403 U.S. at 491). See also Bivens, 403 U.S. at 418-419 (Burger, C.J., dissenting) (even assuming the conduct in Coolidge was improper, it "was surely insufficient in nature and extent to justify the drastic result dictated by the suppression doctrine"); Kaplan, supra, 26 Stan. L. Rev. at 1036 ("the police practices revealed in Coolidge V. New Hampshire are hardly incompatible with a moral society; yet letting the defendant in that case go free perhaps is"). /21/ In explaining the essence of the Fourth Amendment, the Court has stated: "(W)here practical, a governmental search and seizure should represent both the efforts of the officer to gather evidence of wrongful acts and the judgment of the magistrate that the collected evidence is sufficient to justify invasion of a citizen's private premises or conversation." United States V. United States District Court, 407 U.S. at 316. /22/ There is no constitutional requirement that an official issuing a warrant be either a judge or a lawyer, so long as the official is neutral and capable of assessing probable cause. See Shadwick V. City of Tampa, 407 U.S. 345, 348-350 (1972). In the federal system, however, magistrates will usually be trained and experienced lawyers. Thus, the Federal Magistrates Act, 28 U.S.C. (&Supp. V) 631 et seq., requires, with limited exceptions, that all magistrates have practiced law for five years (28 U.S.C. (Supp. V) 631(b)(1)), that they be selected pursuant to merit selection procedures (28 U.S.C. (Supp. V) 631(b)(2)), and that they attend special training programs (28 U.S.C. 637). Although neither constitutionally required nor necessary to give rise to the preference that reviewing courts extend to a magistrate's determinations, we think these salutory features enhance the presumption of propriety that applies to a federal magistrate's probable cause determinations. These same enhancing considerations also apply to the warrant in the instant case, which was issued by a state court judge. /23/ Moreover, because the exclusionary rule "is a judicially created remedy designed to safeguard Fourth Amendment rights generally through its deterrent effect, rather than a personal constitutional right of the party aggrieved," Calandra, 414 U.S. at 348, strict adherence to the rule is both unnecessary and unwise because suitable and efficacious substitute remedies, less costly to society, are available, at least in the federal system. A United States Magistrate, unlike a law enforcement officer, is subject to the control and direction of the district court and may be removed by the court for "incompetency, misconduct, neglect of duty, or physical or mental disability." 28 U.S.C. (Supp. V) 631(i). If it appears that a particular magistrate is serving merely as a "rubber stamp" or had demonstrated an inability to exercise mature judgment, a remedy is available that is far more direct and effective, and less costly to the criminal justice system, than the suppression of evidence in a later proceeding. /24/ Because one object of the officers' suspicion in this case was an automobile, the police were not constitutionally obliged to obtain a warrant for that part of their proposed search. See, e.g., Chambers V. Maroney, 399 U.S. 42 (1970). Their decision to seek prior judicial approval for the search of the automobile is indicative of their good faith. /25/ As Judge Wilkey has observed, "it is all important that there is nevery any question of reliability in exclusionary rule cases involving material evidence * * *. An illegal search in no way reduces the reliability of the evidence." Wilkey, The Exclusionary Rule: Why Suppress Valid Evidence", 62 Judicature 215, 222 (1978). /26/ See, e.g., The Exclusionary Rule Bills: Hearings on S. 101, S. 751 and S. 1995 Before the Subcomm. on Criminal Law of the Senate Comm. on the Judiciary, 97th Cong., 1st Sess. 35-37 (1981) (testimony of Stephen H. Sachs); 1 W. LaFave, Search and Seizure Section 1.2 n.9, at 1 (Supp. 1982). /27/ The declination rate may well be an inappropriate measurement from which to draw meaningful conclusions concerning the effects of the exclusionary rule. Declinations may be low because relatively few federal cases involve manifestly illegal searches. Assistant United States Attorneys may thus choose to go forward in a significant number of cases that have search and seizure problems that may be assessed as troublesome but worth litigating. This hypothesis is borne out by the frequency with which suppression motions are denied (GAO Report 10). /28/ The GAO Report also confined its analysis to cases handled during the two-month period from July 1 through August 31, 1978. GAO recognized that this time period might produce seasonal distortions because of summer vacations, but it did not believe that the variations would be material. GAO Report 17. There is, of course, no way of telling whether the time period selected for the study did in fact affect its outcome. /29/ NIJ also found that declinations due to search and seizure issues were much higher in large urban areas than on a statewide basis. In San Diego County, 8.5% of the declinations in 1980 were due to search and seizure problems. In two Los Angeles area District Attorneys' offices, 11.7% and 14.6% of the 1981 declinations were for search and seizure problems. NIJ Report 1. /30/ The NIJ study probides no data on convictions, as opposed to arrests and declinations. The decision to focus on arrests was "due to inconsistencies in recording dispositional information on the police files of the defendants in (the) samples." NIJ Report 8. /31/ Crimes against persons or property, as defined in the NIJ study, included assault, murder, rape, robbery, burglary, grand theft and grand auto theft. NIJ Report 16. /32/ We do not venture to predict that modification of the exclusionary rule will, by itself, ensure reduction of the crime rate to a material extent. Rather, as a Department of Justice representative testified before Congress (Statement of D. Lowell Jensen, Assistant Attorney General, Criminal Division, United States Department of Justice, Before the Subcomm. on Criminal Justice of the House Comm. on the Judiciary, 97th Cong., 2d Sess. 3 (June 2, 1982)): Any thoughtful consideration of contemporary crime must recognize, unfortunately, that there are no panaceas. On the other hand, advocates for reform (of the exclusionary rule) do point out that the rule operates to free known murderers, robbers, drug traffickers and other violent and non-violent offenders and that a rule of evidence which has such a result without a reasonable purpose to support it is intolerable. /33/ It may be significant in this regard that "no other civilized country has adopted our mandatory rule of the exclusion of probative material evidence because of police misconduct." Wilkey, supra, 1 Crim. Just. Ethics at 23. Moreover, the decision of other countries not to adopt an exclusionary rule has come only after careful and deliberate study. See, e.g., id. at 23-24 & nn. 26-35. /34/ Prompted by the belief "that any remedy for the violation of a constitutional right should be proportional to the magnitude of the violation," the Attorney General's Task Force on Violent Crime has recommended the adoption of a reasonable good-faith exception to the exclusionary rule. Attorney General's Task Force on Violent Crime, Final Report 55-56 (1981). /35/ Judge Wilkey has made the same point, perhaps more graphically, dissenting in United States V. Ross, supra, 655 F.2d at 1208: (The) penalty (of the exclusionary rule) is administered with a sense of proportionality reminiscent of those medieval penal systems that prescribed capital punishment for everything from pickpocketing on up. The rule falls mercilessly on evidence deemed to have been seized unconstitutionally, without regard for the gravity of the police misconduct or the seriousness of the crime of which the defendant has been charged. Even if the policeman's actions were only marginally in violation of the Constitution despite his good faith while the criminal is guilty of rape and murder, still the evidence stays out. Such a disproportion would be regarded as barbaric if used to deter crime; ironically, employed to deter the police many apparently consider it "progressive." /36/ The Court has recognized the same point in holding that public officials enjoy at least qualified immunity in civil damage actions brought under 42 U.S.C. (Supp. IV) 1983. In Scheuer V. Rhodes, 416 U.S. 232, 242 (1974), the Court observed: Implicit in the idea that officials have some immunity -- absolute or qualified -- for their acts, is a recognition that they may err. The concept of immunity assumes this and goes on to assume that it is better to risk some error and possible injury from such error than not to decide or act at all. /37/ The workload generated by the exclusionary rule does not, of course, cease at the trial court level. For example, Judge Wilkey has pointed out that, over a three-year period, 22.1% of the published opinions of the United States Court of Appeals for the District of Columbia Circuit in criminal cases involved suppression issues. M. Wilkey, Enforcing the Fourth Amendment by Alternatives to the Exclusionary Rule 95 F.R.D. 211, 220 (1982). And, during this Term alone, this Court will hear argument in no fewer than 11 cases involving Fourth Amendment search and seizure issues. Texas V. Brown, No. 81-419; Illinois V. Gates, No. 81-430; United States V. Villamonte-Marquez, No. 81-1350; United States V. Place, No. 81-1617; Florida V. Brady, No. 81-1636; United States V. Knotts, No. 81-1802; Illinois V. Andreas, No. 81-1843; Illinois V. Lafayette, No. 81-1859; Florida V. Royer, No. 80-2146; Florida V. Casal, No. 81-2318; Michigan V. Long, No, 82-256. These 11 cases represent nearly half of the 25 criminal cases the Court is likely to hear this Term. This expenditure of judicial resource on suppression issues continues unabated even though "the general principles applicable to claims of Fourth Amendment violations are well settled * * *." Arkansas V. Sanders, 442 U.S. 753, 757 (1979). The most plausible explanation for this phenomenon, of course, is that the windfall benefits of the exclusionary rule for guilty defendants are so great that they effectively negate the likelihood of meaningful self-screening. /38/ See, e.g., Sachs, The Exclusionary Rule: A Prosecutor's Defense, 1 Crim. Just. Ethics 28, 32 (1982). /39/ The Fifth Circuit apparently envisions the good-faith exception as entailing both a subjective and an objective prong, see United States V. Williams, 622 F.2d at 841 n.4a, whereas the New York Court of Appeals believes the test should be strictly objective, see People V. Adams, 53 N.Y.2d at 9-10, 422 N.E.2d at 541. This Court has determined, for reasons only partially applicable in the present context, that the good-faith defense in civil damage actions for alleged constitutional torts should have only an objective component. Harlow V. Fitzgerald, No. 80-945 (June 24, 1982). It has mentioned but not resolved the question with respect to the exclusionary rule in Scott V. United States, 436 U.S. 128, 135-136 (1978). In our view, the test should probably be only objective, for it seems unlikely that there will be many occasions on which a reasonable officer could have entertained a good-faith belief that his action was proper, but the particular officer did not do so; the inclusion of a subjective component will therefore rarely alter the result but would instead merely produce burdensome and largely unproductive litigation. It is possible, however, to imagine cases in which the objective reasonableness of a belief in the legality of particular conduct could be overcome by a showing that, for example, the victim of the search was singled out for harassment. In such circumstances, a subjective inquiry might be appropriate. Plainly, no such circumstances exist here, so decision of this point is not essential to the Court's present task. /40/ Even if additional burdens were imposed, Judge Friendly has suggested that they would be preferable to the current system (H. Friendly, Benchmarks, supra, at 262: It is no sufficient objection that such a rule would require courts to make still another determination; rather the recognition of a penumbral zone where mistake will not call for the drastic remedy of exclusion would relieve them of exceedingly difficult decisions whether an officer overstepped the sometimes almost imperceptible line between a valid arrest or search and an invalid one. Even if there were an added burden, most judges would prefer to discharge it than have to perform the distasteful duty of allowing a dangerous criminal to go free because of a slight and unintentional miscalculation by the police. /41/ Amsterdam, Search, Seizure, and Section 2255: A Comment, 112 U.Pa.L.Rev. 378, 389 (1964). /42/ United States V. Ajlouny, 629 F.2d at 841-842, offers a good example of a court's sound exercise of discretion in declining to decide the legality of a search in light of the applicability of a good-faith exception. The legal question involved warrantless national security wiretaps. Subsequent to the surveillance of Ajlouny, the Foreign Intelligence Surveillance Act of 1978, 50 U.S.C. (Supp. IV) 1801-1811, became effective. That Act, by requiring prior court approval for nearly all foreign intelligence surveillance, "substantially reduced the importance of deciding in this case whether the Constitution independently requires the obtaining of a warrant for foreign intelligence electronic surveillance" (629 F.2d at 842). Accordingly, the court disposed of the case by relying on the good-faith exception. /43/ The courts of appeals routinely exercise similar discretion in applying the harmless error doctrine. Compare, e.g., United States V. West, 670 F.2d 675, 684-687 (7th Cir. 1982); United States V. Bulman, 667 F.2d 1374, 1382-1384 (11th Cir. 1982); Harryman V. Estelle, 616 F.2d 870, 879 (5th Cir. 1980) (en banc); United States V. Rosales-Lopez, 617 F.2d 1349, 1355-1356 (9th Cir. 1980), aff'd, 451 U.S. 182 (1981), with, e.g., United States V. McCulley, 673 F.2d 346, 352 (11th Cir. 1982); United States V. Civella, 666 F.2d 1122, 1130 (8th Cir. 1982); United States V. Torres, 659 F.2d 1012, 1013 (9th Cir. 1981), cert. denied, 455 U.S. 926 (1982).