NATIONAL TREASURY EMPLOYEES UNION, ET AL., PETITIONERS V. WILLIAM VON RAAB, COMMISSIONER, UNITED STATES CUSTOMS SERVICE No. 86-1879 In the Supreme Court of the United States October Term, 1987 On Writ of Certiorari To The United States Court of Appeals for the Fifth Circuit Brief for the United States TABLE OF CONTENTS Question Presented Opinions below Jurisdiction Statement A. The Customs Service drug-testing program B. The present controversy Introduction and summary of argument Argument: The Customs Service drug-testing program is constitutional under the Fourth Amendment A. A warrantless search may be valid even in the absence of particularized suspicion B. The Customs drug-testing program involves a minimal intrusion on employees' expectation of privacy 1. The employment relationship 2. The provision of notice and the elimination of official discretion 3. The narrowly-tailored nature of the testing procedures C. The Customs drug-testing program serves compelling governmental interests Conclusion OPINIONS BELOW The opinion of the court of appeals (Pet. App. 1a-27a) is reported at 816 F.2d 170. The opinion of the court of appeals on the government's motion for a stay pending appeal (Pet. App. 29a-39a) is reported at 808 F.2d 1057. The opinion of the district court (Pet. App. 40a-60a) is reported at 649 F. Supp. 380. JURISDICTION The judgment of the court of appeals was entered on April 22, 1987. The petition for a writ of certiorari was filed on May 27, 1987, and was granted on February 29, 1988. The jurisdiction of this Court rests on 28 U.S.C. 1254(1). QUESTION PRESENTED Whether under the Fourth Amendment the Customs Service may require all employees applying for a transfer to any position involving the the interdiction of narcotics, the carrying of firearms, or the handling of classified material, to undergo a urinalysis drug test as a condition of obtaining such a position. STATEMENT A. The Customs Service Drug-Testing Program 1. The Customs Service, a bureau of the Department of the Treasury, is "the nation's primary border enforcement agency" and "is charged with the responsibility for interdicting illegal drugs that enter the country" (J.A. 109). In fiscal year 1987 alone, Customs agents made over 18,000 narcotics and dangerous drug seizures, representing drugs with a retail value of nearly 9 billion dollars. Customs USA, Fiscal Year 1987, at 40. Recognizing the surge in drug trafficking in the last several years, "Congress recently responded in a manner not unlike a response to a military threat, appropriating over $1 billion (an increase of 26.4% from the last fiscal year) to the Customs Service for fiscal year 1987 with funding for 1000 additional Customs Service personnel" (Pet. App. 35a). In carrying out their mission, Customs employees intercept smugglers (see, e.g., 19 U.S.C. 482, 1581; United States v. Villamonte-Marquez, 462 U.S. 579, 582-583 (1983); United States v. McMurray, 747 F.2d 1417, 1419 (11th Cir. 1984)), perform surveillance (see, e.g., United States v. Johns, 469 U.S. 478, 480 (1985); United States v. Caicedo-Guarnizo, 723 F.2d 1420, 1421 (9th Cir. 1984); United States v. Porter, 701 F.2d 1158, 1160 (6th Cir.), cert. denied, 464 U.S. 1007 (1983)), operate sophiscated equipment (see e.g., United States v. Carter, 760 1985); Porter, 701 F.2d at 1160; United States v. Lueck, 678 F.2d 895, 896-897 (11th Cir. 1982)), execute searches and seizures (see, e.g., 19 U.S.C. (& Supp. IV) 482, 1594, 1595; Villamonte-Marquez, 462 U.S. at 583; Carter, 760 F.2d at 1572-1573; 462 U.S. at 583; Carter, 760 F.2d at 1572-1573; United States v. Sarda-Villa, 760 F.2d 1232, 1235 (11th Cir. 1985)), interrogate suspects (see, e.g., McMurray, 747 F.2d at 1419; United States v. Vega-Barvo, 729 F.2d 1341, 1343 (11th Cir.), cert. denied, 469 U.S. 1088 (1984); United States v. Gomez-Diaz, 712 F.2d 949 (5th Cir. 1983), cert. denied, 464 U.S. 1051 (1984)), make arrests (see, e.g., 19 U.S.C. (& Supp. IV) 1589; Johns, 469 U.S. at 481; Villamonte-Marquez, 462 U.S. at 583), perform undercover work (see, e.g., 19 U.S.C. (& Supp. IV) 2081; United States v. Hall, 739 F.2d 96, 98-99 (2d Cir. 1984)), apply force where necessary (see, e.g., 19 U.S.C. 1581(a); Villamonte-Marquez, 462 U.S. at 580), gather and make use of classified information (United States v. Mitchell, 812 F.2d 1250, 1252 (9th Cir. 1987); United States V. Sanders, 663 F.2d 1, 1-2 (2d Cir. 1981)), and testify in trials and other public proceedings (see, e.g., Gomez-Diaz, 712 F.2d at 951). Throughout that process, "Customs employees are routinely exposed to actual illegal substances and confidential information relating to drug enforcement" (J.A. 109). Drug smuggling is also a violent business, and as a result "many Customs employees are required to carry and use firearms in connection with their official duties" (ibid.). "During 1986 alone, Customs Officers were the victims of assault on 32 occasions, and were shot at on 15 different occasions. Since 1974, nine officers have died in the line of duty." J.A. 110. 2. In December 1985, recognizing that the Customs Service's "primary enforcement mission is drug interdiction" (J.A. 10), respondent, the Commissioner of Customs, established a Drug Screening Task Force "to research all facets of drug screening" and "to determine its applicable use within Customs" (J.A. 11). After several months of study, during which the Task Force engaged in extensive research and consulted with experts in the field, the Commissioner reported that the Service was considering the implementation of a drug screening program within Customs (J.A. 10-12). The Commissioner explained (J.A. 10) that "there is no room in the Customs Service for those who break the laws prohibiting the possession and use of illegal drugs." And while the Commission "believe(d) that Customs is largely drug-free" (ibid.), he noted that "unfortunately no segment of society is immune to the threat of illegal drug use." On May 8, 1986, the Commissioner announced the implementation of the Customs Service drug-testing program (J.A. 15-19). He explained that drug tests would be made "a condition of placement/employment" for positions that meet "one or more of the following criteria: direct involvement in drug interdiction and enforcement of related laws; a requirement that the incumbent carry firearms; or, a requirement for the incumbent to handle classified material" (J.A. 17, 19). The Commissioner also stated (J.A. 19) that a refusal to take the test would "only result in a loss of consideration for the position." /1/ In selecting the three categories of positions for which drug testing would be required, the Commissioner found (J.A. 113) that employees involved in drug interdiction "are often placed in difficult, dangerous situations where the success of the mission, their own life, and the lives of co-workers depend() upon their ability to think and react clearly and quickly." The use of narcotics, he stated (ibid.), "dulls the ability to think and react quickly, clouding the employee's judgment and endangering other lives and government property." /2/ In addition, the Commissioner found (ibid.) that "(p)ublic safety demands that employees who carry deadly arms and are prepared to make instant life or death decisions be drug free. There is no reason why the public must bear the risk that public officials authorized to employ deadly force may be suffering from impaired perception and judgment." Finally, the Commissioner determined (J.A. 114) that employees who use illegal drugs and who are given access to classified material "may be bribed into disclosing such information to a criminal drug enterprise, and they may have a financial need to exchange information valuable to smugglers in order to support their habit." /3/ 3. On August 4, 1986, following negotiations with petitioner National Treasury Employees Union (see J.A. 6, 45-51), the Commissioner issued Directive No. 51250-02, embodying the terms and conditions of the Customs Service drug-testing program (J.A. 23-44). Subsequently on April 11, 1988, in compliance with recently enacted legislation (Supplemental Appropriations Act, 1987, Pub. L. No. 100-71, Section 503, 101 Stat. 468-471), the Department of Health and Human Services (HHS) issued detailed regulations governing all federal employee drug-testing programs. See Mandatory Guidelines for Federal Workplace Drug Testing Programs, 53 Fed. Reg. 11979 (1988) (hereinafter HHS Reg.). Although those regulations are substantially similar to the Customs Directive, there are some respects in which the regulations add to, or differ from, the procedures set out in the Directive. In compliance with the federal statute (Section 503(b)(2)(B), 101 Stat. 470), the Customs Service will shortly be amending its Directive to incorporate the terms of the HHS regulations. As supplemented (and, to a limited extent, supplanted) by the HHS regulations, /4/ the Customs drug-testing program operates in the following way: a. After an employee qualifies for a position covered by the Customs program, the Service advises him by letter (see J.A. 81-85) of his tentative selection (J.A. 26). In that letter, the Service emphasizes that final selection for the job "is contingent upon successful completion of drug screening through urinalysis (and any other pre-employment/placement conditions such as medical examination (and) background investigation * * *" (J.A. 26-27). On an arranged date, the employee is met by a sample collector (an independent contractor) and presents a photo identification (J.A. 28; HHS Reg. Section 2.2(f)(2)). The employee may list on a designated pre-test form any medications taken within the last 30 days and explain any circumstances under which he may have been in legitimate contact with illegal substances within the last 30 days (J.A. 29, 86-87). Provision of this information is voluntary (J.A. 87). /5/ On the same form, the employee must also indicate, by his signature, that he understands that successful completion of the drug test is a condition of employment; that if the results of the test indicate use of illegal drugs, he may lose consideration for the position applied for and, if he is already a Customs employee, may be subject to removal from the Service; and that if he refuses to take the test, he will lose consideration for the position applied for (J.A. 29, 86). /6/ b. When the actual testing takes place, the employee is asked to remove his outer garments (such as coats and jackets) and to leave all personal belongings, other than a wallet, with the outer garments (J.A. 29; HHS Reg. Section 2.2(f)(4)). Observation is "close" but not "direct" (J.A. 29): the employee may provide his specimen in the privacy of a stall (HHS Reg. Section 2.2(f)(7)), and the Service has carefully instructed its contractors to obey that restriction (J.A. 96-97). /7/ After the urine specimen is collected, the employee hands it to the collector, who measures the temperature of the urine to be sure that it has not been adulterated and that there has been no substitution for the employee's own urine (HHS Reg. Section 2.2(f)(12)). The collector then places a tamper-proof custody seal over the top and down the sides of the bottle. In addition, a urine identification label is completed and placed around the bottle, indicating the date and the individual's specimen number. The employee then signs a chain-of-custody form, which is initialed by the collector, and the urine specimen is placed in a plastic bag, sealed tightly, and submitted to a laboratory, J.A. 30-31; HHS Reg. Section 2.2(f)(19), (20), (24), (25), (g), and (h). Next, the employee's pre-test form is placed in a sealed envelope bearing the employee's social security number and is sent to a Customs Drug Screening Coordinator. That envelope is not opened unless and until there has been a positive finding on the drug test. If the test proves negative, the envelope and its contents are destroyed. J.A. 30-31. c. The laboratory to which the samples are submitted must be managed by an individual who is either certified as a laboratory director in forensic or clinical laboratory toxicology, or who has a Ph.D. in one of the natural sciences, or who has training and experience comparable to a Ph.D. in one of the natural sciences (HHS Reg. Section 2.3(a)(1) and (2)). This individual must also have direct experience in "analysis of biological materials for drugs of abuse" (id. Section 2.3(a)(2)(iv)). The laboratories must maintain a security system (id. Section 2.4(a)(1)) and follow detailed chain-of-custody procedures (id. Section 2.4(a)(2)). The Secretary of HHS, as well as the Customs Service itself, has the right to inspect the laboratory at any time (id. Section 2.4(a)(1)), and the laboratory must maintian and make available, for at least two years, documents on all aspects of the testing process (id. 2.4(m)). In addition, the regulations set forth elaborate quality assurance and control procedures (id. Section 2.5), including thorough use of blind samples (id. Section 2.5(d)). /8/ They also prescribe standards for laboratory filing systems (id. Section 2.3(f)), training (id. Section 2.3(e)), refrigerated storage of speciments (id. Section 2.4(c) and (h)), and reporting of results (id. Section 2.4(g)). /9/ Once the samples are submitted to the laboratory, they are analyzed for the presence of marijuana (cannabinoids), cocaine, opiates, amphetamines, and phencyclidine (J.A. 32). "In response to concern that specimens may be misused to test for physiological states other than drug abuse (e.g., pregnancy)" (53 Fed. Reg. 11975 (1988)), HHS Reg. Section 2.1(c) expressly provides that urine specimens "shall be used only to test for those drugs included in agency drug-free workplace plans and may not be used to conduct any other analysis or test unless otherwise authorized by law." Two tests are conducted on the samples. There is an initial screening test that uses the enzyme-multiplied-immunoassay technique (EMIT) (J.A. 32; HHS Reg. Section 2.4(e)(I)). Any specimen that is identified as positive on the initial test must then be confirmed using gas chromatography/mass spectrometry (GC/MS) (J.A. 32; HHS Reg. Section 2.4(f)(1)). No sample is considered to be positive unless it is positive on the GC/MS test (HHS Reg. Section 2.4(g)(2)). It is generally conceded that a properly conducted GC/MS test is essentially 100 percent accurate in detecting for the presence of drug residues in urine. See J.A. 62 (affidavit of John P. Morgan, M.D.); J.A. 65 (affidavit of Dr. Arthur J. McBay); J.A. 105 (declaration of Walter F. Vogl). Indeed, "(b)oth parties agree that GC/MS provides a highly accurate test for the presence of drugs, assuming proper handling, storage, and testing techniques" (Pet. App. 5a). d. After the samples have been analyzed, the laboratory reports its results to a "Medical Review Officer," who must be "(a) licensed physician * * * who has knowledge of substance abuse disorders and has appropriate medical training to interpret and evaluate an individual's positive test result together with his or her medical history and any other relevant bio-medical information" (HHS Reg. Sections 1.2, 2.4(g)). The Medical Review Officer must "review and interpret positive test results" before any such results may be transmitted to the agency (id. Section 2.7(a) and (b)). The Medical Review Officer must examine "alternate medical explanations for any positive test result"; in doing so, he may interview the employee, review the employee's medical records, or consider other biomedical factors (id. Section 2.7(b)). Before verifying a positive test result, the Medical Review Officer must offer the employee an opportunity to discuss the result (id. Section 2.7(c)). The Medical Review Officer may also order a reanalysis of the original sample "(s)hould any question arise as to the accuracy or validity of a positive test result" (id. Section 2.7(e)). After verifying the positive result, the Medical Review Officer transmits it to the agency. e. If there is no legitimate explanation of the positive test result, Customs employees are subject to loss of consideration for the position sought, as well as possible removal from the Service (J.A. 35). /10/ The test results, however, may not be turned over to any other agency, including criminal prosecutors, without the employee's prior written consent. See n.6, supra. B. The Present Controversy 1. On August 12, 1986, petitioners -- a federal employees' union and a union officer -- brought this action in the United States District Court for the Eastern District of Louisiana, alleging that the Customs Service drug-testing program violated the Fourth Amendment (J.A. 3-9). Petitioners asserted that the collection of urine samples is a "search" within the meaning of the Fourth Amendment (J.A. 7) and that it is unreasonable "because there is no evidence of significant use of illegal drugs amongst Customs employees, because the procedure will not identify those employees who do not use illegal drugs, because the tests will result in false positive readings, and because the tests are invasive and will be administered without any particularized suspicion" (J.A. 8). /11/ The district court held the Customs Service program unconstitutional on numerous grounds (Pet. App. 40a-60a). The court first found that the drug-testing program deprived job applicants of their Fourth Amendment right to be free from unreasonable searches and seizures, in that it uses "a dragnet approach of testing all workers who seek promotion into so-called 'covered positions'" (id. at 51a). Although the court agreed that the Service sought to accomplish a "legitimate" goal, it concluded that "the massive intrusive effect of the drug testing plan" outweighed the governmental interests (ibid.). The court next found (id. at 54a-55a) that the Customs program violated employees' Fifth Amendment privilege against self-incrimination, explaining (id. at 55a) that the tests "constitute() a degrading procedure that so detracts from human dignity and self respect that it "shocks the conscience" and offends th(e) Court's sense of justice." The Court also held (id. at 55a-56a) that the drug-testing program violates employees' "penumbral" right of privacy and that it is "so fraught with dangers of false positive readings as to deny the Customs workers due process of law" (id at 58a). The court enjoined the drug-testing program, forbidding the Customs Service to require drug tests of any applicants for the covered positions (id. at 61a-62a). 3. The court of appeals reversed (Pet. App. 1a-27a). /12/ The court noted that petitioners did not seek to defend the district court's judgment on privacy-rights grounds (id. at 20a). It also had no difficulty rejecting the claims that the drug-testing program involves compelled self-incrimination (id. at 19a-20a) and that it is so unreliable as to violate due process (id. at 21a). The court further ruled, in the only holding that petitioners challenge here, that the Customs Service drug-testing program is valid under the Fourth Amendment (id. at 6a-19a). In so holding, the court of appeals agreed with petitioners that the drug-testing program -- by requiring an employee to submit a urine sample and testing the sample for evidence of drug use -- effects a search within the meaning of the Fourth Amendment (Pet. App. 6a-9a). The court held, however, that the program is reasonable and therefore constitutional. It first noted (id. at 11a) that "(t)he Service has attempted to minimize the intrusiveness of the search" by forbidding the direct observation of the collection process and by affording notice to the employee that a drug test will be given. /13/ Indeed, the court explained (id. at 14a), because the test "is required only from those individuals who voluntarily seek employment in a covered position knowing in advance of the urinalysis requirement," the drug-testing program "is, to some extent, consensual." Also minimizing the intrusivenss of the search, the court found (id. at 14a-15a), is the fact that the Customs program is an aspect of an employment relationship. "Government employees may be subject to searches or other restraints on their liberties that would be impermissible in the absence of the employment relationship" (id. at 14a); and the court found (id. at 15a) that "(c)onsidering the nature and responsibilities of the jobs for which applicants are being considered at Customs and the limited scope of the search, the exaction of consent as a condition of assignment to the new job is not unreasonable." Arrayed on the other side of the balance, the court discerned a "strong governmental interest in employing individuals for key positions in drug enforcement who themselves are not drug users" (Pet. App. 2a). The court found (id. at 12a) that "(t)he use of illicit drugs has had a pernicious impact on American society" and it agreed (id. at 13a) that the "(u)se of controlled substances by employees of the Customs Service may seriously frustrate the agency's efforts to enforce the drug laws." In particular, the court explained (ibid. (footnotes omitted)), "(a)n employee's use of the substances he has been hired to interdict casts substantial doubt upon his ability to carry out his duties honestly and vigorously, and undermines public confidence in the integrity of the Service." Moreover, the court noted (ibid.), "(t)he drug user's questionable integrity, as well as the high financial cost of obtaining illegal drugs, may increase his susceptibility to bribery by criminal drug enterprises seeking classified information." In addition, the court stated (ibid.), "those employees involved in field operations, particularly if carrying firearms, endanger the safety of their fellow agents, as well as their own, when their performance is impaired by drug use." Finally, the court rejected the contentions that there are less intrusive measures available and that the Customs program is not a sufficiently effective means of determining drug use in covered positions (id. at 17a-19a). /14/ Considering "the totality of circumstances" and "weighing all of the factors" (id. at 11a), the court of appeals held that individualized suspicion is not required in this setting and that "the Customs Service program for testing employees who seek a transfer to sensitive positions is not unreasonable" (id. at 19a). Judge Hill dissented (Pet. App. 23a-27a). In his view, "the program at issue in this case is an ineffective method for achieving the Customs Service's goals, and thus it is an unreasonable invasion of the Customs Service's employees' fourth amendment rights" (id. at 23a). Judge Hill noted (id. at 25a) that under the program at issue persons already employed in sensitive positions were not subject to the test. In addition, he surmised (id. at 26a), "once a tested employee is accepted into a covered position, he is never tested again." "Finally, and most importantly," Judge Hill explained (ibid.), "employees given a five day notification of a test date need only abstain from drug use to prevent being identified as a user." Because, in his judgment, the Customs program cannot achieve its purposes, Judge Hill found it to be unreasonable under the Fourth Amendment. On May 12, 1987, the court of appeals denied petitioners' request for a stay and ordered immediate issuance of the mandate (Pet. App. 28a). On June 1, 1987, this Court denied petitioners' application for a stay, Justice Brennan dissenting (No. A-847). INTRODUCTION AND SUMMARY OF ARGUMENT "Illicit trafficking in drugs," Congress has declared, "is one of the most serious crime problems facing the country." H.R. Rep. 98-1030, 98th Cong., 2d Sess. 255 (1984). The Customs Service is in many ways the first line of defense in the struggle against narcotics. To foster the efficiency, integrity, and public accountability of its employees, the Service has adopted a narrowly tailored, carefully crafted drug-testing program as a condition of placement in specific sensitive positions. The court of appeals, after weighing all of the competing factors, correctly concluded that the Customs drug-testing program is reasonable under the Fourth Amendment, even though it does not require a showing of probable cause or particularized suspicion of drug use. A. "The fundamental command of the Fourth Amendment is that searches and seizures be reasonable" (New Jersey v. T.L.O., 469 U.S. 325, 340 (1985)), and "what is reasonable depends on the context within which a search takes place" (id. at 337). The reasonableness of a particular search practice "is judged by 'balancing its intrusion on the individual's Fourth Amendment interests against its promotion of legitimate governmental interests.'" United States v. Montoya de Hernandez, 473 U.S. 531, 537 (1985) (citation omitted). Applying this balancing test, the Court has emphasized that a search may be reasonable under the Fourth Amendment in the absence of either a warrant or probable cause. Moreover, the Court has explained, although "some quantum of individualized suspicion is usually a prerequisite to a constitutional search or seizure(,) * * * the Fourth Amendment imposes no irreducible requirement of such suspicion." United States v. Martinez-Fuerte, 428 U.S. 543, 560-561 (1976) (footnote omitted). Thus, the Court has on several occasions identified exceptions to the requirement of particularized suspicion "where the privacy interests implicated by a search are minimal and where 'other safeguards' are available 'to assure that the individual's reasonable expectation of privacy is not "subject to the discretion of the official in the field"'" (New Jersey v. T.L.O., 469 U.S. at 342 n.8 (citations omitted)). We believe that the balance of competing interests strongly supports the constitutionality of the Customs drug-testing program -- even though it requires no particularized suspicion of drug use. B. The Customs drug-testing program makes only the most minimal intrusion on employees' reasonable expectations of privacy. Three features of the program account for that fact. First and most generally, the Customs drug testing program is an aspect of an ongoing employment relationship. While public employees do not forfeit Fourth Amendment rights by virtue of their employment with the government, "(t)he employee's expectation of privacy must be assessed in the context of the employment relation." O'Connor v. Ortega, No. 85-530 (Mar. 31, 1987), slip op. 7. In our view, employees -- particularly those, like Customs employees, whose basic mission is to stem the surge in illegal drugs -- have good reason to expect their employer to attempt to create a drug-free workplace for sensitive positions. Second and more specifically, the Customs drug tests are administered only to employees who have applied, and have been tentatively accepted, for promotion or transfer to one of the three categories of covered positions. Applicants know at the outset that a drug test is a requirement of those positions, and they pursue their applications with the certain knowledge that successful completion of a drug test is a condition of ultimately obtaining the job. By structuring the drug tests in this fashion, the Customs Service affords notice to employees and eliminates any role in the system for official discretion. Under this Court's cases, those factors substantially reduce the intrusiveness of the tests. Third, the drug testing procedures themselves are narrowly tailored to respect, to the fullest extent practicable, the employees' reasonable expectations of privacy. Employees are notified in advance of the scheduled sample collection, and the collection process itself provides maximum feasible privacy. The urinalysis procedures are highly reliable; elaborate safeguards are followed to ensure accurate results; and participating laboratories must meet exacting quality assurance standards. While the process of providing a specimen may provoke, in some employees, a measure of self-consciousness, there is no warrant for the suggestion, repeatedly urged by petitioners, that the Customs Service drug-testing program is "frightening, embarassing, offensive to personal integrity, or some combination thereof" (Pet. Br. 21). C. While the intrusion on privacy is minimal, the governmental interests at stake are substantial. Customs has a surpassing interest in ensuring that its employees are able to perform their mission efficiently; that they are insulated from threats of blackmail or corruption; and that the Service is, and is perceived by the public to be, untainted by drug use. Petitioners' contention that those goals cannot be achieved is erroneous and overlooks the government's prerogative to proceed toward its objectives one step at a time. And petitioners' suggestion that there are "less intrusive" alternatives available is both legally irrelevant and factually without support. ARGUMENT THE CUSTOMS SERVICE DRUG-TESTING PROGRAM IS CONSTITUTIONAL UNDER THE FOURTH AMENDMENT A. A Warrantless Search May Be Valid Even In The Absence Of Particularized Suspicion 1. "The fundamental command of the Fourth Amendment is that searches and seizures be reasonable * * *." New Jersey v. T.L.O., 469 U.S. 325, 340 (1985). See United States v. Montoya de Hernandez, 473 U.S. 531, 537 (1985); United States v. Villamonte-Marquez, 462 U.S. 579, 588 (1983). Thus, the Fourth Amendment "does not denounce all searches and seizures, but only such as are unreasonable." Carroll v. United States, 267 U.S. 132, 147 (1925). The test of reasonableness moreover, "is not capable of precise definition or mechanical application." Bell v. Wolfish, 441 U.S. 520, 559 (1979). Rather, in defining the contours of the right to be free from unreasonable searches and seizures, this Court has repeatedly said that "'the specific content and incidents of this right must be shaped by the context in which it is asserted.'" Wyman v. James, 400 U.S. 309, 318 (1971) (quoting Terry v. Ohio, 392 U.S. 1, 9 (1968)). See also New Jersey v. T.L.O., 469 U.S. at 337 ("what is reasonable depends on the context within which a search takes place"). The Court has articulated a balancing test to govern this inquiry. "The permissibility of a particular law enforcement practice is judged by 'balancing its intrusion on the individual's Fourth Amendment interests against its promotion of legitimate governmental interests.'" United States v. Montoya de Hermandez, 473 U.S. 531, 537 (1985) (quoting United States v. Villamonte-Marquez, 462 U.S. 579, 588 (1983)). See also Delaware v. Prouse, 440 U.S. 648, 654 (1979); Camara v. Municipal Court, 387 U.S. 523 (1967). This approach recognizes that not every invasion of privacy is prohibited by the Fourth Amendment, but only "arbitrary and oppressive interference by enforcement officials with the privacy and personal security of individuals." United States v. Martinez-Fuerte, 428 U.S. 543, 554 (1976). "Where a careful balancing of governmental and private interests suggests that the public interest is best served by a Fourth Amendment standard of reasonableness that stops short of probable cause, (the Court has) not hesitated to adopt such a standard" (New Jersey v. T.L.O., 469 U.S. at 341). In examining the competing interests, the Court has often found a third consideration important -- the amount of discretion left to the officials carrying out the search. See, e.g., Donovan v. Dewey, 452 U.S. 594, 601-604 (1981); Delaware v. Prouse, 440 U.S. at 654, 661; Marshall v. Barlow's, Inc., 436 U.S. 307, 320-321 (1978). See also Colorado v. Bertine, 479 U.S. 367, 376-377 (1987) (Blackmun, J., concurring). Because this constraint on discretion derives from the constitutional requirement of "reasonableness" (Delaware v. Prouse, 440 U.S. at 654), the means needed to confine discretion also necessarily vary from context to context. What is required to meet the constitutional concern for controlling discretion depends on the strength of the governmental interest in a particular search practice and the impairment of privacy interests that the practice effects. 2. Applying this balancing test, the Court has held that in the context of an ordinary investigation of criminal conduct by law enforcement officers, both probable cause and a warrant are generally necessary to render a search reasonable. See United States v. Karo, 468 U.S. 705, 717 (1984); United States v. United States District Court, 407 U.S. 297, 317 (1972). But as the Court explained most recently in Griffin v. Wisconsin, No. 86-5324 (June 26, 1987), slip op. 4 (citation omitted), exceptions from those requirements have been permitted "when 'special needs, beyond the normal need for law enforcement, make the warrant and probable-cause requirement impracticable.'" See New Jersey v. T.L.O., 469 U.S. at 340 (quoting Almeida-Sanchez v. United States, 413 U.S. 266, 277 (1973) (Powell, J., concurring)) ("although 'both the concept of probable cause and the requirement of a warrant bear on the reasonableness of a search, * * * in certain limited circumstances neither is required'"). Where, for example, "the burden of obtaining a warrant is likely to frustrate the governmental purpose behind the search" (Camara v. Municipal Court, 387 U.S. at 533), the Court has routinely held that a warrant is not required by the Fourth Amendment. In Griffin v. Wisconsin, supra, the Court held that a probation officer need not obtain a warrant before conducting a search of a probationer's residence. The Court explained that a warrant requirement "would interfere to an appreciable degree with the probation system, setting up a magistrate rather than the probation officer as the judge of how close a supervision the probationer requires" (slip op. 7). Similarly, in New Jersey v. T.L.O., holding that school officials did not need a warrant or probable cause to search a child suspected of an infraction of school disciplinary rules, the Court found that a warrant requirement "would unduly interfere with the maintenance of the swift and informal disciplinary procedures needed in the schools" (469 U.S. at 340). See also O'Connor v. Ortega, No. 85-530 (Mar. 31, 1987), slip op. 11 (plurality opinion) ("requiring an employer to obtain a warrant whenever the employer wished to enter an employee's office, desk, or file cabinets for a work-related purpose would seriously disrupt the routine conduct of business and would be unduly burdensome"). The Court has likewise found that the probable cause standard is inappropriate where it would defeat the purposes that the search is designed to achieve. For example, in the Griffin case the Court found that holding probation officials to a probable cause standard "would reduce the deterrent effect of the supervisory arrangement" (slip op. 9). Similarly, in rejecting a probable cause requirement in O'Connor, a plurality of the Court explained (slip op. 13-14) that "(t)he delay in correcting the employee misconduct caused by the need for probable cause rather than reasonable suspicion will be translated into tangible and often irreparable damage to the agency's work, and ultimately to the public interest." See also New Jersey v. T.L.O., 469 U.S. at 340-342. 3. In still other contexts, the Court has recognized that a warrantless search may be reasonable even in the absence of any individualized suspicion of unlawful conduct. As the Court explained in United States v. Martinez-Fuerte, 428 U.S. at 560-561 (footnote omitted), although "some quantum of individualized suspicion is usually a prerequisite to a constitutional search or seizure(,) * * * the Fourth Amendment imposes no irreducible requirement of such suspicion." See also New Jersey v. T.L.O., 469 U.S. at 342 n.8; Camara v. Municipal Court, supra. For example, the Court has held that no individualized suspicion is required for the Coast Guard or Customs Service to board a vessel and to examine its owner's documents. United States v. Villamonte-Marquez, supra. Similarly, in Wyman v. James, 400 U.S. 309, 318 (1971), the Court upheld the right of a welfare caseworker to enter the home of a welfare recipient to ensure compliance with welfare rules, even though the statute authorizing the home visit required no showing that the recipient was out of compliance with the rules. And in United States v. Martinez-Fuerte, supra, the Court held that border officials may stop automobiles at permanent checkpoints without any individualized suspicion. Each of these cases reflects the Court's statement in T.L.O. that "(e)xceptions to the requirement of individualized suspicion are generally appropriate only where the privacy interests implicated by a search are minimal and where 'other safeguards' are available 'to assure that the individual's reasonable expectations of privacy is not "subject to the discretion of the official in the field"'" (469 U.S. at 342 n.8 (citations omitted)). As we show below, the Customs drug-testing program amply satisfies that standard. B. The Customs Drug-Testing Program Involves a Minimal Intrusion on Employees' Expectation of Privacy 1. The employment relationship A first and quite general feature of the Customs drug-testing program, which significantly minimizes its interference with expectations of privacy, is the fact that the test is conducted as an aspect of the employment relationship. While "(i)ndividuals do not lose Fourth Amendment rights merely because they work for the government instead of a private employer(,) * * * (t)he operational realities of the workplace * * * may make some employees' expectations of privacy unreasonable" (O'Connor v. Ortega, slip op. 6 (emphasis in original)). Thus, "(t)he employee's expectation of privacy must be assessed in the context ofthe employment relation" (id. at 7). In the Ortega case, for example, the plurality found that the search of an employee's office "'involve(d) a relatively limited invasion'" of privacy, noting that "the privacy interests of government employees in their place of work * * *, while not insubstantial, are far less than those found at home or in some other contexts" (slip op. 14). More generally, this Court has consistently recognized that the government, in its capacity as an employer, may impose reasonable employment-related restrictions on the rights of employees that would be plainly unconstitutional if imposed on citizens at large. See, e.g., Rankin v. McPherson, No. 85-2068 (June 24, 1987), slip op. 5; Connick v. Meyers, 461 U.S. 138, 147 (1983); Snepp v. United States, 444 U.S. 507, 509 n.3 (1980); United States Civil Service Comm'n v. National Ass'n of Letter Carriers, 413 U.S. 548 (1973). Put another way, "the government's interest as an employer in fit employees may allow it to deny employment when it cannot as a sovereign attac(h) other consequences to the protected view" (Pet. App. 38a). /15/ This proposition has particular force in the context of the Customs Service. When they accept a position with the Service, especially a sensitive position, Customs employees necessarily commit themselves to the mission of the agency -- to enforce the narcotics laws. By its nature, that mission entails a number of important restrictions on their liberties. Customs employees may be asked to take on difficult and dangerous tasks. They may be subject while they are in the field and in another way when they give testimony in court. In short, employees may be, and routinely are, required to comport themselves in ways that conform to the requirements of the agency. That does not mean, of course, that Customs employees lack any cognizable zone of privacy. It does suggest, however, that Customs employees should not find it "frightening, embarassing, (and) offensive to personal integrity" (Pet. Br. 21) when their employing agency -- which is sworn to enforce the narcotics laws, to protect the public, and to safeguard classified information from threats of blackmail or corruption -- decides to promote its mission by insisting on a reasonable procedure to promote a drug-free workplace for specific sensitive positions. 2. The provision of notice and the elimination of official discretion A second, and more specific, feature of the Customs program, which also minimizes its intrusiveness on employees' privacy, is the fact that the testing is "a condition of placement/employment in the specified positions" (J.A. 19). Thus, an employee who applies for a covered position knows at the outset that a drug test is a prerequisite for obtaining the job; after he is tentatively selected, the employee is advised by letter that "(c)ontinued consideration for th(e) position is contingent upon satisfactory completion of a drug screening test" (J.A. 81). Moreover, although an applicant who refuses to take the test will lose consideration for the position sought, his subsequent applications will not be affected: no adverse actions will be taken against him, and no documentation adversely affecting subsequent applications will be maintained (J.A. 36). By structuring its drug-testing program in this fashion, Customs has minimized the intrusion on employees' reasonable expectations of privacy in two central respects. a. First, by giving its employees advance notice of the test, Customs reduces to a minimum any "unsettling show of authority" (Delaware v. Prouse, 440 U.S. at 657) that may be associated with unexpected intrusions on privacy. Unlike the subject of an arrest warrant, who may be aroused unexpectedly by police at his doorstep (see Payton v. New York, 445 U.S. 573 (1980)), or a driver, who may experience "substantial anxiety" from a "sporadic and random stop()" of his automobile" (Prouse, 440 U.S. at 657), a Customs employee has the certain knowledge that drug testing comes with the job. For those reasons, the court of appeals concluded (Pet. App. 14a) that "(t)he Customs Service test is, to some extent, consensual"; and as this Court has many times explained, "a search authorized by consent is wholly valid." Schneckloth v. Bustamonte, 412 U.S. 218, 222 (1973). See also United States v. Matlock, 415 U.S. 164 (1974). This Court's decision in Zap v. United States, 328 U.S. 624 (1946), vacated on other grounds, 330 U.S. 800 (1947), makes that point in a closely related context. There, the petitioner, a defense contractor, had entered into an agreement with the Navy Department to perform experimental work on airplane wings. The agreement specified that the contractor's books and records would be available at all times for review by the government. During the life of the contract, FBI agents conducted an audit of the petitioner's records, and evidence discovered in that audit was later introduced against the petitioner at trial. This Court held that the government's audit did not violate the Fourth Amendment. The Court explained (328 U.S. at 628) that "when petitioner, in order to obtain the Government's business, specifically agreed to permit inspection of his accounts and records, he voluntarily waived such claim to privacy which he otherwise might have had as respects business documents related to those contracts." The Court concluded (id. at 629) that the agents "were lawfully on the premises" and had "obtained by lawful means access to the documents. That much at least was granted by the contractural agreement for inspection." /16/ But even if the employee's consent to the drug test does not altogether eliminate any Fourth Amendment concern, it certainly minimizes any cognizable intrusion on privacy. This Court's decision in Wyman v. James, 400 U.S. 309 (1971), confirms the point. In Wyman, the Court held that the Fourth Amendment did not preclude welfare caseworkers from visiting the homes of welfare recipients to ensure compliance with the welfare program. Although the statute in question did not require any allegation that the recipients were abusing the welfare system, the Court found no violation of the Fourth Amendment. Indeed, because of the consensual nature of the visits, the Court was not persuaded that the visits constituted searches at all. The Court noted (id. at 317-318) that "the visitation in itself is not forced or compelled, and that the beneficiary's denial of permission is not a criminal act. If consent to the visitation is withheld, no visitation takes place. The aid then never begins or merely ceases, as the case may be. There is no entry of the home and there is no search." In any event, the Court explained, even if the caseworker's visit might be construed as a search ("perhaps because the average beneficiary might feel she is in no position to refuse consent to the visit" (id. at 318)), the visits were nevertheless reasonable. In so holding, the Court found (id. at 320) that "(t)he means employed" to make the searches were "significant," in that the recipient was given "written notice several days in advance of the intended home visit" (ibid. (footnote omitted)). The Court explained that this feature "minimize(d) any 'burden' upon the homeowner's right against unreasonable intrusion" (id. at 321). /17/ Here, as in Wyman, The Customs Service drug tests are not "forced or compelled." If consent to the test is refused, the employee suffers no penalty, other than forfeiting consideration for the covered position at that time. The Service creates no permanent record of the refusal, nor is any adverse action taken against the employee. As the Court put the matter in Wyman, affording notice and making participation voluntary "minimizes any 'burden' upon the (employee's) right against unreasonable intrusion." /18/ See also National Fed'n of Fed. Employees v. Weinberger, 818 F.2d 935, 943 (D.C. Cir. 1987); Shoemaker v. Handel, 795 F.2d 1136, 1142 (3d Cir.), cert. denied, 479 U.S. 986 (1986); Security & Law Enforcement Employees, District Council 82 v. Carey, 737 F.2d 187, 201-202 & n.23 (2d Cir. 1984). b. Second, by subjecting all applicants to a drug test as a condition of transfer to a covered position, the Customs Service has eliminated any official discretion from its drug-testing program. This Court has explained that "(t)he essential purpose of the proscriptions in the Fourth Amendment is to impose a standard of 'reasonableness' upon the exercise of discretion by government officials, including law enforcement agents, in order '"to safeguard the privacy and security of individuals against arbitrary invasions * * *"'" (Delaware v. Prouse, 440 U.S. at 653-654(footnote and citations omitted)). /19/ Thus, as the Court stated in Prouse, "(i)n those situations in which the balance of interests precludes insistence upon 'some quantum of individualized suspicion,' other safeguards are generally relied upon to assure that the individual's reasonable expectation of privacy is not 'subject to the discretion of the official in the field'" (440 U.S. at 655 (footnote omitted) (quoting Camara v. Municipal Court, 387 U.S. at 532)). See also New Jersey v. T.L.O., 469 U.S. at 342 n.8. Under the Customs program, every employee who seeks to transfer to a covered position must take a drug test. The Service has no discretion in that regard. It may not carve out exceptions; nor may it select particular employees, but not others, to test. Every test is conducted in the same way, is analyzed the same way, and is reported the same way. "The urinalysis results are either positive or negative leaving no room for official discretion in interpreting the tests" (Pet. App. 11a-12a (footnote omitted)). Indeed, the principal discretion in the entire process is exercised by the employee -- when he elects to apply for, and thereafter pursue, a covered position, knowing that a drug test will eventually be required. Like the police inventory searches upheld in South Dakota v. Opperman, 428 U.S. 364 (1976), "no significant discretion is placed in the hands of the individual officer," who has "no choice as to the subject of the search or its scope" (id. at 384 (Powell, J., concurring) (footnote omitted)). See also Colorado v. Bertine, 479 U.S. at 376-377 (Blackmun, J., concurring). c. These same factors -- the provision of notice and the elimination of discretion -- persuaded this Court, in United States v. Martinez-Fuerte, 428 U.S. 543 (1976), to uphold under the Fourth Amendment the stopping of vehicles at permanent checkpoints in the absence of any individualized suspicion that the particular vehicle contained illegal aliens. Finding that the "intrusion on Fourth Amendment interests is quite limited" (id. at 557), the Court explained (id. at 559), first, that motorists "are not taken by surprise as they know, or may obtain knowledge of, the location of the checkpoints and and will not be stopped elsewhere." Second, the Court stated (ibid.), "checkpoint operations both appear to and actually involve less discretionary enforcement activity. The regularized manner in which established checkpoints are operated is visible evidence, reassuring to law-abiding motorists, that the stops are duly authorized and believed to serve the public interest." The Court concluded that "(a)s the intrusion here is sufficiently minimal(,) * * * no particularized reason need exist to justify it" (id. at 563). We believe that the same principles control this case. Here, as in Martinez-Fuerte, employees are "not taken by surprise" when they are asked to take a drug test. They know about the test before they seek a transfer and they are reminded about the test after they have been tentatively selected for a position. Moreover, because the test is given to all applicants, the drug-test program "both appear(s) to and actually involve(s) less discretionary enforcement activity." The intrusion on privacy, as in Martinez-Fuerte, is therefore "sufficiently minimal that no particularized reason need exist to justify it." /20/ 3. The narrowly-tailored nature of the testing procedures Finally, the actual procedures employed by the Customs Service, as supplemented by the recently promulgated HHS regulations, are narrowly tailored to respect employees' reasonable expectations of privacy. Applicants are notified by letter that a drug test will be required (J.A. 26-27, 81-85), and an independent contractor thereafter contacts the employee to schedule the sample collection. At the time of the collection, the employee is asked, as petitioners put it, "to divulge personal medical information, including all medications of any kind taken within the last thirty days" (Pet. Br. 20); but that information remains sealed unless and until there is a confirmed positive result from the drug test, and is then used only to rebut, if possible, the inference of illegal substance abuse (J.A. 30-31). In addition, if the employee wishes to withhold medical information at this point, he may do so, without placing any restriction on his ability to later reveal this information in confidence to the Medical Review Officer to explain a positive test result. See n.5, supra. The actual collection process is not directly observed; the employee provides a specimen in the privacy of a stall (J.A. 29; HHS Reg. Section 2.2(f)(7)). The collector then measures the temperature of the sample to ensure that it has not been adulterated, places a tamper-proof seal over the bottle, prepares a chain-of-custody form, and submits the bottle to the laboratory (J.A. 30-31; HHS Reg. Section 2.2.(f)(12), (19), (20), (24), (25), (g) and (h)). The laboratory, in turn, must be specially certified (see nn.8, 9, supra), must follow strict chain-of-custody procedures, must perform confirmatory analyses of the samples (conceded by all parties to be reliable), and must submit its results to a Medical Review Officer, who only after confirming the findings reports them to the agency (HHS Reg. Sections 2.4(a)(2), (f)(1) and (g), 2.5., 2.7(a), (b) and (c), 3.17, 3.18; J.A. 32; Pet. App. 5a). We acknowledge that some persons may feel self-conscious about the actual collection process; if no one did, it would be hard to locate any expectation of privacy at all. But, through petitioners' lens, that momentary self-consciousness is magnified into a process that is at once "frightening, embarassing, offensive to personal integrity, or some combination thereof," causing an "apprehension * * * at the prospect of having one's urine captured and analyzed" (Pet. Br. 21). Those metaphors, however, greatly exaggerate the extent to which the Customs program deviates from the ordinary daily experience of the typical Customs employee. Customs employees are required to produce a urine specimen in a private stall; but virtually all employees use public restrooms in every working day for their own bodily needs. The collecting official remains within earshot of the stall and listens for the urination; but other persons can and routinely do overhear others engaged in excretory functions during the normal work day, and there is no special right of privacy for activities that persons routinely allow others to overhear. Cf. California v. Ciraolo, 476 U.S. 207, 213 (1986); Smith v. Maryland, 442 U.S. 735 (1979); United States v. Miller, 425 U.S. 435, 443, (1976). And while persons do not reasonably expect others to intrude into their private space during the process of urination, Customs collectors do not do so either. Indeed, the Customs Service has carefully instructed its contractors to respect the privacy of its employees (J.A. 96-97). Thus, as Judge Higginbotham concluded below, "(t)he precise privacy interest asserted is elusive" in this case, since "apart from the partial disrobing (apparently not independently challenged) persons using public toilet facilities experience a similar lack of privacy" (Pet. App. 36a). /21/ In our view, the Customs collection process, while perhaps novel in terms of the narrowness of its focus, is not materially different from any number of medical and physical examinations required by employers in the public and private sectors as a condition of employment. /22/ The federal government, for one, routinely requires applicants for jobs with particular physical or medical demands to submit to physical examinations (5 C.F.R. 339.301(a)(1)) and imposes the same requirement, on a regularly recurring basis, on current employees in those positions (5 C.F.R. 339.301(a)(2)). We are advised, for example, that criminal investigators, specialists, and auditors for the Bureau of Alcohol, Tobacco, and Firearms must undergo complete physical exams, including a urine test for sugar levels; special agents, operations support technicians, protective support technicians, special officers, and motor vehicle operators for the Secret Service likewise undergo a comprehensive physical, including blood and urine testing; motor vehicle operators, police officers, printing plant workers, and industrial power truck operators for the Government Printing Office are given routine physicals as a condition of employment; and border patrol agents, criminal investigators, and immigration inspectors for the Immigration and Naturalization Service are given pre-employment physicals that include blood and urine tests. The courts have approved such tests when imposed as a reasonable condition of employment. See, e.g., McDonell v. Hunter 612 F. Supp. 1122, 1130 n.6 (S.D. Iowa 1985), aff'd, 809 F.2d 1302 (8th Cir. 1987). Cf. Bratcher v. United States, 149 F.2d 742, 745-746 (4th Cir.), cert. denied, 325 U.S. 885 (1945). As Judge Higginbotham explained below (Pet. App. 36a), "the information gained in tests of urine is not different from that disclosed in medical records, for which consent to examine is a routine part of applications for many sensitive government posts." Petitioners contend, however, that the collection process infringes employees' right "to control both the timing and the ultimate disposition of his own waste" (Br. 22 n.16). But again, petitioners overstate the strength of that interest. As Judge Higginbotham observed (Pet. App. 36a), "(f)inding an objectively reasonable expectation of privacy in urine, a waste product, contains inherent contradictions." Like the disposal of trash, which the Court in California v. Greenwood, No. 86-684 (May 16, 1988), recently held to be outside one's reasonable expectation of privacy, urine is only briefly "possessed", if at all, and is quickly abandoned. To be sure, persons expect to dispose of urine on their own terms; but the interference with that ephemeral interest, we suggest, is minor, hardly warranting what petitioners extravagantly term "the apprehension one feels at the prospect of having one's urine captured and analyzed" (Br. 21). /23/ Petitioners also contest the Customs program because, in their view (Br. 28-29), the physical examination of the urine sample has "the potential for the revelation of anatomical secrets hidden in urine" including a "wealth of information" such as "pregnancy, epilepsy, or diabetes, treatment of psychiatric disorders, use of contraceptives, or other personal information." The Customs Directive makes clear, however, that the drug test may be used to discern only specified illegal drugs (J.A. 32). And the HHS regulations expressly forbid participating laboratories from testing for any other substances (HHS Reg. Section 2.1(c)) -- a prohibition included in the regulations specifically "(i)n response to concern that specimens may be misused to test for physiological states other than drug use (e.g., pregnancy)" (53 Fed. Reg. 11975 (1988)). Since that proscription is easy to obey -- both by refusing to make the prohibited analyses and by maintaining the anonymity of the individual samples at the laboratory -- there is no warrant for petitioners' assumption that the government will violate its own regulations, and that employees' "anatomical secrets" will thereby be compromised. Cf. INS v. Miranda, 459 U.S. 14, 18 (1982)(per curiam) (presumption of regularity supports official act of public officer); Citizens to Preserve Overton Park, Inc. v. Volpe, 401 U.S. 402, 415 (1971) (same); United States v. Chemical Found, Inc., 272 U.S. 1, 14-15 (1926) (same). The fact that urine specimens are tested only for the presence of illegal narcotics eliminates any claim that the process of analysis itself intrudes on any legitimate privacy interests. This Court has held that a laboratory analysis that tests only for unlawful substances is not a "search" at all within the meaning of the Fourth Amendment. See United States v. Jacobsen, 466 U.S. 109, 123 (1984); United States v. Place, 462 U.S. 696 (1983). Consequently, the only part of the drug-testing process that even implicates Fourth Amendment interests is the collection of urine specimens. And as we have already demonstrated, because of the multiple safeguards built into the process -- including advance notice, the elimination of any significant measureof discretion, and the narrowly tailored nature of the testing procedures themselves -- the impact of the Customs program on privacy interests is minimal indeed. C. The Customs Drug-Testing Program Serves Compelling overnmental Interests 1. "As the record demonstrates, and as the whole nation knows, traffic in illegal drugs with its enormous destruction of life is a national problem" of surpassing importance (Pet. App. 35a). "Illicit trafficking in drugs," Congress has declared, "is one of the most serious crime problems facing the country." H.R. Rep. 98-1030, 98th Cong., 2d Sess. 255 (1984). This Court's cases tell a small but representative part of the story. They trace the path of narcotics from the ships and airplanes (see, e.g., United States v. Villamonte-Marquez, 462 U.S. 579 (1983); United States v. Montoya de Hernandez, 473 U.S. 531 (1985)), across the country (see, e.g., Illinois v. Gates, 462 U.S. 213 (1983)), to the streets of the inner cities (see, e.g., Bourjaily v. United States, No. 85-6725 (June 23, 1987); Maryland v. Garrison, No. 85-759 (Feb. 24, 1987); United States v. Ross, 456 U.S. 798 (1982)), and the classrooms of the nation's schools (see, e.g., New Jersey v. T.L.O. supra). They recount, if briefly, the elaborate schemes for importing narcotics (see, e.g.; United States v. Ramsey, 431 U.S. 606 (1977)), the "highly sophisticated narcotics * * * network(s)" that control its manufacture and distribution (Jeffers v. United States, 432 U.S. 137, 139 (1977) (plurality opinion); see also Garrett v. United States, 471 U.S. 773 (1985)), and the hundreds of laboratories and distribution outlets, across the country, that produce, package, and market the drugs to the consuming public. See, e.g., United States v. Dunn, No. 85-998 (Mar. 3, 1987); Henderson v. United States, 476 U.S. 321 (1986); Segura v. United States, 468 U.S. 796 (1984). And they tell, unfortunately, of the random, senseless violence that is in every sense a tool of the trade. See, e.g., Booth v. Maryland, No. 86-5020 (June 15, 1987); Richardson v. Marsh, No. 85-1433 (Apr. 21, 1987); Allen v. McCurry, 449 U.S. 90 (1980). See also United States v. Alvarez, 810 F.2d 879, 892-897 (9th Cir. 1987) (Noonan, J., dissenting) (collecting cases). The Customs Service is in many ways the first line of defense in the nation's struggle with narcotics. As "the nation's primary border enforcement agency," the Service "is charged with the responsibility for interdicting illegal drugs that enter the country" (J.A. 109). To ensure that the Service is able to discharge that responsibility, the Commissioner has approved a narrowly tailored drug-testing program that focuses on positions that directly involve the employee to carry firearms, or that require the employee to handle classified material. The Customs drug-testing program serves three vital purposes. First among these is the safe and efficient discharge of Customs operations. /24/ As the Commissioner found (J.A. 113), "(i)llegal drug use dulls the ability to think and react quickly, clouding the employee's judgment and endangering other lives and government property." Studies have indicated that drug abusers typically function at only fifty to sixty-seven percent capacity; that they suffer a rate of absenteeism ranging between 2.5 and 16 times higher than employees who do not use drugs; and that they have a significantly higher turnover rate, leaving their jobs, on average, between 10 and 16 months earlier than employees who do not use drugs. See Rothstein, Drug Testing in the Workplace: The Challenge to Employment Relations and Employment Law, 63 Chi(-)Kent L. Rev. 683, 688-689 & nn.23, 25, 29 (1987) (citing studies). Drug abusers are likely to show "inadequate preparation, impaired memory, lethargy, reduced coordination, carelessness, mistakes, and slowdowns" (id. at 688 (footnote omitted), citing studies). And as the court of appeals observed (Pet. App. 13a), "those employees involved in field operations, particularly if carrying firearms, endanger the safety of their fellow agents, as well as their own, when their performance is impaired by drug use." In addition, the Customs drug-testing program promotes the integrity of Customs operations. As the Commissioner has explained (J.A. 114), employees who use illegal drugs "may be bribed into disclosing (classified) information to a criminal drug enterprise, and they may have a financial need to exchange information valuable to smugglers in order to support their habit." Indeed, the Commissioner observed (ibid.), "(g)iven the incredible sums of money involved, it is not surprising that Customs Officers have been the targets of bribery by drug smugglers on numerous occasions, and several Customs Officers have been removed for accepting such bribes and other integrity violations in past years." While we certainly agree with petitioners that the overwhelming majority of Customs employees "only, seek the opportunity to serve their country in its battle against traffic in illegal drugs" (Pet. Br. 48) 48), no one, including including petitioners, disputes that there are, and will continue to be exceptions to that rule, particularly as Customs fulfills the congressional mandate to augment its ranks considerably (see J.A. 114). /25/ See, e.g., United States v. Hall, 739 F.2d 96 (2d Cir. 1984); Masino v. United States, 589 F.2d 1048 (Ct. Cl. 1978). Cf Heron V. McGuire, 803 F.2d 67, 68 (2d Cir. 1986) (per curiam). Finally, the Customs Service has a substantial interest in ensuring that its employees do not damage the agency's public reputation. This Court has several times recognized the importance of that interest. For example, in Snepp v. United States, 444 U.S. 507, 509, n.3(1980), the Court held that the Central Intelligence Agency has a "compelling interest" in maintaining "the appearance of confidentiality so essential to the effective operation of our foreign intelligence service." Similarly, in sustaining the Hatch Act against First Amendment challenge, the Court held that Congress has a substantial interest, not only in ensuring that federal service employees "in fact avoid practicing political justice," but also in ensuring "that they appear to the public to be avoiding it." United States Civil Service Commission v. National Ass'n of Letter Carriers, 413 U.S. 548, 565 (1973). And in sustaining the Lloyd-La Follette Act (5 U.S.C. 7501) against First Amendment challenge, the Court upheld a federal regulation (5 C.F.R. 735.201a(f)) providing that a civil servant may be removed for engaging in expressive activity that "(a)ffect(s) adversely the confidence of the public in the integrity of the Government." Arnett v. Kennedy, 416 U.S. 134, 141-142(1974). In each of these cases, the Court recognized that the government has an overriding interest in regulating employee behavior "which improperly damages and impairs the reputation and efficiency of the employing agency" (id. at 162). As a law enforcement agency, Customs naturally has a strong and legitimate interest in maintaining the reputation and appearance of being fully committed to enforcement of the law. It depends on the public for tips about criminal activity and for testimony in support of its enforcement efforts. Customs officers must themselves frequently testify in trials and other public proceedings in which the credibility of the officers, and of the agency generally, is critically at issue. Perhaps most importantly, Customs relies on the public for voluntary compliance with the letter of the law. To maintain this spirit of cooperation, Customs may properly insist that its employees possess the highest standards of professional conduct, on and off the job. For if a law enforcement agency and its employees do not take the law seriously, neither will the public on which the agency's effectiveness depends. See Olmstead v. United States, 277 U.S. 438, 485 (1928) (Brandeis, J., dissenting) ("For good or for ill, (our Government) teaches the whole people by its example."). 2. Petitioners acknowledge (Br. 39-40) that "Customs' stated objective for its plan is an important one" and that its goals are "unexceptionable" (id. at 40). They contend (id. at 46), however, that the program cannot succeed since "virtually anyone who uses illegal drugs can avoid detection by temporary abstinence." Petitioners accordingly surmise that "a search that can so easily be thwarted will not serve as an effective deterrent to prevent illegal drug users from seeking Customs positions" (id. at 46-47). Petitioners overstate the case. As the court of appeals explained, "(a)ddicts may not be able to abstain" prior to the test, and other employees, who "may not * * * be aware of the fade-away effect" of narcotics, may not choose to abstain (Pet. App. 18a). There are also significant differences in how quickly traces of narcotics disappear from the body. The record in this case shows, for example, that while in most cases marijuana becomes undetectable within "two to five days," it may remain in the body considerably longer in cases of "chronic users" (J.A. 60 (affidavit of John P. Morgan)) -- in some instances for as much as 22 or 30 days (J.A. 66 (affidavit of Dr. Arthur J. McBay)). Thus, as the court of appeals found (Pet. App. 18a), "a particular user still faces a significant risk that his test would be positive." That "risk of detection therefore may deter drug-using employees from seeking more sensitive positions" (ibid.). Still other drug users, who choose to abstain temporarily prior to the test, may miscalculate the necessary period of abstention and test positive despite their efforts at evasion. Indeed, notwithstanding the notice provision, at least five applicants have produced positive urine samples since the inception of the Customs drug-testing program (Pet. Br. 8). But even if the Customs drug-testing program cannot ferret out every abuser, that does not make it unreasonable under the Fourth Amendment. To be sure, by affording employees notice of the drug test, the Customs Service may have allowed some drug users to evade the test. But, by furnishing notice, the Service has also reduced the intrusiveness of the process. Customs was entitled to strike the balance -- plainly a reasonable one -- that it thought was appropriate under the circumstances. Here, as elsewhere, the government "may take one step at a time, addressing itself to the phase of the problem which seems most acute." Williamson v. Lee Optical, 348 U.S. 483, 489 (1955). /26/ 3. Petitioners also contend (Br. 35 (footnote omitted)) that "Customs has not demonstrated that a probable cause standard would prevent its investigating and punishing workplace wrongdoing." Alternatively, petitioner's argue (Br. 37-48) that Customs must meet a "reasonable suspicion" standard before conducting a drug test. As a threshold matter, we do not see why, in light of the balance of competing interests, the Customs program should be measured by either standard. As this Court explained in the T.L.O. case, "(w)here a careful balancing of governmental and private interests suggests that the public interest is best served by a Fourth Amendment standard of reasonableness that stops short of probable cause, (the Court has) not hesitated to adopt such a standard" (469 U.S. at 341). Accord O'Connor v. Ortega, slip op. 12. The balance of interests in this case places the Customs program squarely within the "(e)xceptions to the requirement of individualized suspicion" -- that is, where "the privacy interests implicated by a search are minimal and * * * 'other safeguards' are available 'to assure that the individual's reasonable expectation of privacy is not "subject to the discretion of the official in the field"'" (New Jersey v. T.L.O., 469 U.S. at 342 n.8). In any event, petitioners endorse probable cause (or at least particularized suspicion) as an appropriate legal standard only by ignoring most of the objectives that Customs seeks to achieve by conducting drug tests of employees in sensitive positions. Probable cause or particularized suspicion may be workable where an agency merely seeks, in petitioners' words, to "punish workplace wrongdoing." But Customs has a broader, and in many respects more important, agenda. It also seeks to deter wrongdoing, to insulate employees from threats to integrity, and to promote the public reputation of the agency. The margin of error associated with a probable cause or particularized suspicion standard is singularly unsuited to those ends. As in United States v. Martinez-Fuerte, imposing either standard would reduce the deterrent effect (see 428 U.S. at 557) of the drug-testing program, by allowing drug users to persist in their habit until sufficient evidence accumulates against them. And if Customs were required to await palpable evidence of misconduct before it could intervene, the result could be an incalculable loss to the agency's enforcement mission and to its public reputation as a law enforcement agency. In view of the minimally intrusive nature of the Customs program, and the surpassing importance of its objectives, there is no basis for requiring the agency to absorb such costs. See O'Connor v. Ortega, slip op. 14. /27/ 4. Finally, petitioners contend (Br. 45) that there are "less intrusive means to address the stated problem," including reliance on "'physical observation * * *, citizen complaints, tips from other law enforcement agencies and other means'" (id. at 35 (citation omitted)). But "(t)he reasonableness of any particular governmental activity does not necessarily or invariably turn on the existence of alternative 'less intrusive' means." Illinois v. Lafayette, 462 U.S. 640, 647, (1983). This Court has cautioned against "indulg(ing) in 'unrealistic second-guessing,'" because "'creative judge(s), engaged in post hoc evaluations of police conduct can almost always imagine some alternative means by which the objectives of the police might have been accomplished'" (United States v. Montoya de Hernandez, 473 U.S. at 542, quoting United States v. Sharpe, 470 U.S. 675, 686-687 (1985)). As the Court has explained, "(t)he logic of such elaborate less-restrictive-alternative arguments could raise insuperable barriers to the exercise of virtually all search-and-seizure powers" (United States v. Martinez-Fuerte, 428 U.S. at 556-557 n.12). Accord Colorado v. Bertine, 479 U.S. at 373-375; Cady v. Dombrowski, 413 U.S. 443, 447 (1973). In any event, petitioners do not explain why their suggested alternatives would be as effective as the Customs drug-testing program. Relying on colleagues and supervisors to detect symptoms of drug use, while of some benefit, cannot suffice. As the Federal Railroad Administration recently observed, after studying the various alternatives at length, "the symptoms of drug use are often undetectable by even a reasonably trained supervisor. Further, some 'functional' drug users seem able to avoid job-related problems until their problems reach a crisis stage." 53 Fed. Reg. 16640 (1988). Moreover, some drugs have "delayed, residual or chronic effects not ascertainable through behavioral observation." Transport Workers' Union, Local 234 v. Southeastern Pennsylvania Transp. Auth., 678 F. Supp. 543, 550 (E.D. Pa. 1988). Accord Schaill v. Tippecanoe County School Corp., 679 F. Supp. 833, 857-858 (N.D. Ind. 1988). Petitioners' preference for observation by co-workers is particularly misplaced in this case, because applicants for sensitive positions have not yet been exposed to the special pressures of a job at the forefront of the drug interdiction effort (and thus cannot have been "observed" under relevant conditions.) /28/ Beyond that, Customs employees often work alone, for example in undercover operations or in other settings in which close observation is difficult. Scrutiny by fellow employees may also be inconsistent with the demands of colleagueship; employees simply may not be willing to report substance abuse by their fellow workers (see Pet. App. 17a-18a). And even were such reporting likely, on-the-job scrutiny can discern only on-the-job impairment; it cannot determine, as drug testing can, the use of narcotics off the premises -- use that is equally inconsistent with the integrity objectives of the Service. /29/ * * * * * In sum, the Customs, drug-testing program is reasonable. Because the program applies only to applicants for sensitive positions; because the program is a reasonable incident of an ongoing employment relationship; because the program offers applicants advance notice that they will be subject to such tests; because the program applies without discretion to all such applicants; and because the program is conducted under carefully circumscribed procedures that minimize the potential for embarassment or abuse, the intrusion on individual expectations of privacy is minimal. At the same time, the program advances governmental interests of the highest order -- protecting the efficient performance, integrity, and reputation of an agency that serves at the front lines in the struggle against illegal drug use. Certainly, employee drug testing is no panacea; it cannot be expected to solve by itself the overwhelming problems of drug abuse that afflict this Nation. But employee drug testing -- when rationally imposed and reasonably conducted -- has the potential of being one important tool in that effort. And as this case demonstrates, a drug-testing program that meets those criteria of reasonableness is fully consistent with the requirements of the Fourth Amendment. CONCLUSION The judgment of the court of appeals should be affirmed. Respectfully submitted, CHARLES FRIED Solicitor General JOHN R. BOLTON Assistant Attorney General THOMAS W. MERRILL Deputy Solicitor General JAMES M. SPEARS ROBERT J. CYNKAR Deputy Assistant Attorneys General LAWRENCE S. ROBBINS Assistant to the Solicitor General LEONARD SCHAITMAN ROBERT V. ZENER Attorneys JAMES H. ANDERSON Attorney United States Customs Service JUNE 1988 /1/ Under the Customs program, an employee who is tentatively selected for a covered position, but who refuses to take a drug test, will lose consideration only for the position for which he has applied. Subsequent applications are not affected by a refusal, nor does the Service maintain any documentation that adversely affects an employee's subsequent applicants. J.A. 36. /2/ The Commissioner also noted (J.A. 113) that "the liberties of other citizens are often dependent on the good judgment of these Customs employees who have the full range of police powers." /3/ The Commissioner stated (J.A. 114) that "(g)iven the incredible sums of money involved, it is not surprising that Customs Officers have been the targets of bribery by drug smugglers on numerous occasions, and several Customs officers have been removed for accepting such bribes and other integrity violations in past years." /4/ Although the HHS regulations were issued after the decision of the court of appeals, they are properly before this Court for review, to whatever extent they supplement or supplant the Customs Directive. As the Court made clear in California Bankers Ass'n v. Shultz, 416 U.S. 21 (1974), this Court "must examine the * * * regulations as they now exist" -- not as they "existed when the District Court (or the court of appeals) ruled in the case" (id. at 53). See Thorpe v. Housing Auth., 393 U.S. 268, 282 (1969). This principle is particularly applicable where, as here, a plaintiff seeks to enjoin a regulatory scheme that has been amended by the newly-issued regulations. /5/ The pre-test form presently states that "(f)ailure to provide this information may prevent the agency from considering the effect of medications taken by an individual on a positive test result" (J.A. 87). This language is, however, inconsistent with the subsequently-issued HHS regulations, which provide that the Medical Review Officer (see pp. 8-9, infra) "shall review all medical records made available by the tested individual when a confirmed positive test could have resulted from legally prescribed medication" (HHS Reg. Section 2.7(b)). Customs plans to delete the inconsistent language from its pre-test form, as part of the revisions necessary to conform to the HHS regulations. /6/ Test results may not be used for purposes of a criminal prosecution. By statute, the test results may not be disclosed to anyone without the employee's prior written consent, except to certain specified officials within the agency or by court order when necessary to defend against any challenge to adverse personnel action. Pub. L. 100-71, Section 503(e), 101 Stat. 471. The purpose of that provision was "to avoid misuse and the possibility of criminal prosecution or any adverse action by any other agency or individual" (133 Cong. Rec. H5680 (daily ed. June 27, 1987) (statement of conferees)). /7/ Indeed, Customs insisted that a drug-testing proposal submitted by a contractor be modified to preclude direct observation of the voiding process (J.A. 91-92). /8/ To be certified to perform drug-testing for federal agencies, a laboratory is subjected to a performance test, requiring it to test three cycles of blind samples over a period of at least three months (HHS Reg. Sections 3.17, 3.18). A single false positive result during this initial performance assessment "will automatically disqualify a laboratory from further consideration" (id. Section 3.19(a)(1)). During the first 90 days following the certification of a laboratory, the agency must submit to the lab "blind performance test speciments * * * in the amount of at least 50 percent of the total number of samples submitted (up to a maximum of 500 samples) and thereafter a minimum of 10 percent of all samples (to a maximum of 250) submitted per quarter" (id. Section 2.5(d)(2)). After certification, laboratories must continue to be "challenged" every other month with a set of at least test speciments (id. Section 3.17(c)). /9/ Before the HHS regulations were proposed, Customs entered into a contract with a private laboratory and has requested a waiver from HHS to continue using that laboratory pending its certification under the guidelines. Customs' laboratory is on the HHS schedule for certification and Customs has no reason to believe that it will not be certified. /10/ A Customs employee who does not wish to challenge a positive finding may voluntarily resign (J.A. 36). /11/ Petitioners did not allege, as they do now (Br. 25-37), that the Fourth Amendment forbids drug testing except where there is a showing of probable cause. Indeed, in the court of appeals petitioners "concede(d) that the Customs Service might test employees who seek transfers if there were some degree of individualized suspicion" (Pet. App. 10a-11a). See also Appellees' Br. 13. /12/ The court addressed petitioners' constitutional challenges only insofar as the drug-testing program applies to current Customs Service employees who seek covered positions; it reversed the district court's judgment as applied to outside job applicants because those persons were not parties to the case (Pet. App. 3a, 21a; Pet. 6 n.9). /13/ The court added (Pet. App. 11a) that the Customs program is "limited in total scope" and "prevent(s) the exercise of discretion concerning who is to be tested" because "(o)nly employees seeking transfer to sensitive positions are required to take the test and only as a result of a process that they choose to set in motion." /14/ The court explained (Pet. App. 17a) that "alternative sources of information do not eliminate the need for urine testing" in part because other Customs employees "may be reluctant to disclose their knowledge of the employee's drug use or may be unaware of (it)" (id. at 18a). And while the court recognized that employees may attempt to deceive the drug test by a brief abstention prior to the examination it noted (ibid.) that "(a)ddicts may not be able to abstain for five days"; that a particular user may show traces of narcotics for a longer than average period; and that many employees may not be aware of the fact that drug traces fade away. The court concluded (ibid.) that "(t)he risk of detection therefore may deter drug-using employees from seeking more sensitive positions." /15/ As Judge Higginbotham observed below (Pet. App. 38a), "(a)n anarchist's political view is protected by the first amendment. But I would not suppose that his constitutional protection extends to the right to be an FBI agent." /16/ See also Davis v. United States, 328 U.S. 582 (1946); United States v. Lopez-Pages, 767 F.2d 776, 779 n.2 (11th Cir. 1985) (air traveler's consent based on notice on sign that passengers are subject to search); United States v. DeAngelo, 584 F.2d 46, 47-48 (4th Cir. 1978) (same), cert. denied, 440 U.S. 935 (1979); United States v. Freeland, 562 F.2d 383, 385-386 (6th Cir.) (same), cert. denied, 434 U.S. 957 (1977); McMorris v. Alioto, 567 F.2d 897 (9th Cir. 1978) (attorney's consent to magnetometer search as condition of entering courthouse); United States v. Silher, 562 F.2d 349, 350-351 (5th Cir. 1977) (prison employee's consent based on notice on sign stating that all persons entering prison are subject to search); United States v. Ellis, 547 F.2d 863 (5th Cir. 1977) (visitors to Naval station may be required to consent to warrantless search of automobile); United States v. Davis, 482 F.2d 893, 913-914 (9th Cir. 1973) (air traveler's consent to pre-boarding search for weapons); United States v. Skipwith, 482 F.2d 1272 (5th Cir. 1973) (same). /17/ The Court has made much the same point in its administrative inspection cases. In United States v. Biswell, 406 U.S. 311 (1972), for example, the Court upheld the statutorily-authorized, warrantless search of the locked storeroom of a licensed gun dealer, which resulted in the seizure of unlicensed firearms. The Court explained (id. at 316 that inspections under the statute "pose only limited threats to the dealer's justifiable expectations of privacy" since "(w)hen a dealer chooses to engage in this pervasively regulated business and to accept a federal license, he does so with the knowledge that his business records, firearms, and ammunition will be subject to effective inspection." See also Michigan v. Tyler, 436 U.S. 499, 514 (1978) (Stevens, J., concurring in part and concurring in the judgment) ("(t)he Fourth Amendment interests involved in this case could have been protected in either of two ways -- by a warrant, if probable cause existed; or by fair notice, if neither probable cause nor a special law enforcement need existed"). At least two courts of appeals have relied on this Court's administrative inspection cases in upholding drug testing programs that did not require a showing of individualized suspicion. See Rushton v. Nebraska Public Power Dist., 844 F.2d 562 (8th Cir. 1988) (nuclear plant engineers); Shoemaker v. Handel, 795 F.2d 1136 (3d Cir.), cert. denied, 479 U.S. 986 (1986) (race track employees). But see Railway Labor Executives' Ass'n v. Burnley, 839 F.2d 575 (9th Cir. 1988), cert. granted, No. 87-1555 (June 6, 1988). /18/ For many of the same reasons, it may also be argued, as this Court concluded in Wyman (400 U.S. at 317-318), that the Customs drug-testing program is not a Fourth Amendment search at all. Federal government employees routinely submit to fingerprint checks, full field background investigations, physical examinations and, for employees engaged in national security functions, questioning subject to polygraphs as conditions of employment. These employment tests involve differing degrees of intrusiveness into an employee's privacy as well as exercises of dominion and control, albeit slight, over the employee. Nonetheless, we are aware of no decision holding that such tests, when imposed as a reasonable condition of employment, interfere with reasonable expectations of privacy or otherwise raise Fourth Amendment questions. See McDonell v. Hunter, 612 F. Supp. 1122, 1130 n.6 (S.D. Iowa 1985), aff'd, 809 F.2d 1302 (8th Cir. 1987). Cf. Brachter v. United States, 149 F.2d 742 (4th Cir.), cert. denied, 325 U.S. 885 (1945) (routine, warrantless preinduction physical upheld); Schlagenhauf v. Holder, 379 U.S. 104, 114 (1964) (physical examination required of defendant under Fed. R. Civ. P. 35 is "free of constitutional difficulty"). Moreover, here, as in Wyman, the test is a prerequisite for the receipt of particular benefits that may freely be accepted or declined. The employee knows of the test in advance and participates in it, at his option, as he might in any other pre-employment examination. Accordingly, in our view Wyman is persuasive authority for the proposition that an employee drug-testing program -- containing these or substantially similar features -- does not entail "any search by the (government) in the Fourth Amendment meaning of that term" (400 U.S. at 317). To resolve that issue, however, would require this Court to render a decision with broader implications that the facts of this case demand. We are therefore content to rest our defense of the Customs program on the essential reasonableness of the program itself. /19/ See also United States v. Ortiz, 422 U.S. 891, 895-896 (1975); United States v. Brignoni-Ponce, 422 U.S. 873, 882 (1975). /20/ We do not mean to suggest that the Customs program -- which limits official discretion by subjecting all persons selected for designated sensitive position to a test -- is the only constitutionally acceptable means of limiting official discretion. Post-accident testing, such as that at issue in Burnley v. Railway Labor Executive's Ass'n, No. 87-1555, also effectively restricts official discretion. In addition, the government is presently defending particular drug testing programs that involve random selection of employees for testing according to neutral criteria (such as Social Security number or birth date). American Federation of Government Employees v. Dole, No. 87-5417 (D.C. Cir.) (air traffic controllers and certain other Department of Transportation employees); National Federation of Federal Employees v. Carlucci, Nos. 88-5080, 88-5081, 88-5082 (D.C. Cir.) (Department of the Army employees occupying aviation positions, security guards, law enforcement positions, employees involved with chemical warfare or nuclear materials, alcohol and drug abuse counselors, and employees at Army forensic drug testing laboratories). See Adams, Random Drug Testing of Government Employees: A Constitutional Procedure, 54 U. Chi. L. Rev. 1335, 1367-1368 (1987). /21/ Petitioners also exaggerate the nature of urinalysis when they describe it (Br. 32) as an "(i)ntrusion() into the body itself." Unlike a blood test (see Schmerber v. California, 384 U.S. 757 (1966)), the extraction of a bullet (see Winston v. Lee, 470 U.S. 753 (1985)), or even the removal of fingernail scrapings (see Cupp v. Murphy, 412 U.S. 291 (1973)), the urine samples are produced by the employee and turned over to the collector. /22/ Cf. New York Transit Auth. v. Beazer, 440 U.S. 568, 591 n.37 (1979) ("a simple urine test" was sufficient to prove compliance with Transit Authority's rule against employing drug users); Schmerber v. California, 384 U.S. at 771 n.13 (citation omitted) ("'(t)he blood test procedure has become routine in our everyday life. It is a ritual for those going into the military service as well as those applying for marriage licenses. Many colleges require such tests before permitting entrance and literally millions of us have voluntarily gone through the same, though a longer, routine in becoming blood donors'"). /23/ We also dispute petitioners' suggestion (Br. 22 n.16) that the Customs Service "seizes" its employees when it directs them to produce a urine sample as a condition of promotion to a sensitive position. Under this argument, the Fourth Argument would be implicated every time a public employers directed an employee to participate in an employment-related physical examination. Moreover, the direction to provide a urine sample is surely no more of a seizure than the compulsion of a grand jury subpoena -- which is enforceable by contempt -- to produce voice exemplars, handwriting, or fingerprints. And yet this Court has held that such subpoenas are not seizures within the meaning of the Fourth Amendment. See United States v. Dionisio, 410 U.S. 1 (1973); United States v. Mara, 410 U.S. 19 (1973). /24/ This Court noted the importance of that concern in its decision in the Ortega case. There, the Court observed (slip op. 13) that "(p)ublic employers have an interest in ensuring that their agencies operate in an effective and efficient manner, and the work of these agencies inevitably suffers from the inefficiency, incompetence, mismanagement or other work-related misfeasance of its employees. Indeed, in many cases, public employees are entrusted with tremendous responsibility, and the consequences of their misconduct or incompetence to both the agency and the public interest can be severe." /25/ As the Commissioner explained (J.A. 112), the Customs "applicant pool is drawn from a society where drug abuse is widespread" and there is "no reason to believe that this applicant pool is somehow immune to a problem that has pervaded all socio-economic classes of our society." /26/ There is a certain irony to petitioners' argument, because it effectively contends, as the court of appeals put it (Pet. App. 19a), that "the testing program would be more likely to be constitutional if it were more pervasive and more invasive of privacy." In fact, the Customs Service presently contemplates supplementing the current program with a random testing plan for all sensitive employees. The fact that random testing has not yet been implemented does not undercut the reasonableness of the present testing program. /27/ Petitioners also insist on a probable cause or reasonable suspicion standard to reduce the intrusiveness of a program in which, as they estimate it, "99.99 plus % of those searched have been innocent" (Br. 26). The same might be said, we suppose, about the searches of automobiles at fixed checkpoints in Martinez-Fuerte: there, too, the vast majority of cars doubtless did not contain illegal aliens. But as Justice Powell explained in his concurring opinion in South Dakota v. Opperman, 428 U.S. 364, 378 (1976), rejecting a similar challenge to police inventory searches, "the occasional danger that may exist cannot be discounted entirely. * * * The harmful consequences in those rare cases may be great, and there does not appear to be any effective way of identifying in advance those circumstances or classes of automobile impoundments which represent a greater risk." In any event, the high percentage of negative test samples may well be a result of the deterrent value of the drug-testing program itself. /28/ As the court of appeals explained (Pet. App. 17a), "(a)lthough the Service has had an opportunity to observe the performance of employees while they were working non-sensitive positions, this provides scant basis on which to evaluate their integrity and reliability should they be assigned to work in sensitive positions." /29/ Moreover, it is by no means clear that the alternatives proposed by petitioners and the amici supporting them are truly "less intrusive." "(O)n-going observation by * * * supervisors and co-employees" (Pet. Br. 35) could well promote a less private workplace. "Motor coordination tests" and "neuro-behavioral tests" (ACLU Br. 20), whatever their efficacy, are almost assuredly more invasive than drug tests. See also Baker, Letz, & Fidler, A Computer-Administered Neurobehavioral Evaluation System for Occupational and Environmental Epidemiology, 27 J. Occupational Med. 206, 211 (1985) (cautioning that neurobehavioral testing may discriminate against certain groups). Moreover, neither workplace observation nor behavioral tests address the problem of an employee whose off-duty drug use has not affected his on-duty performance but may have rendered him susceptible to bribery or blackmail. And as the court of appeals explained, detailed background investigations, which petitioners also endorse (Pet. Br. 35), may themselves be "intrusive invasions of an individual's privacy" (Pet. App. 18a). See Fraternal Order of Police v. City of Philadelphia, 812 F.2d 105 (3d Cir. 1987) (constitutional challenge to questionnaire given to police officers volunteering for special investigations unit).