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SUPREME COURT OF THE UNITED STATES

No. 93–1660

ARIZONA, PETITIONER v. ISAAC EVANS

on writ of certiorari to the supreme court of arizona

[March 1, 1995]

Chief Justice Rehnquist delivered the opinion of the Court.

This case presents the question whether evidence seized in violation of the Fourth Amendment by an officer who acted in reliance on a police record indicating the existence of an outstanding arrest warrant—a record that is later determined to be erroneous—must be suppressed by virtue of the exclusionary rule regardless of the source of the error. The Supreme Court of Arizona held that the exclusionary rule required suppression of evidence even if the erroneous information resulted from an error committed by an employee of the office of the Clerk of Court. We disagree.

In January 1991, Phoenix police officer Bryan Sargent observed respondent Evans driving the wrong way on a one-way street in front of the police station. The officer stopped respondent and asked to see his driver's license. After respondent told him that his license had been suspended, the officer entered respondent's name into a computer data terminal located in his patrol car. The computer inquiry confirmed that respondent's license had been suspended and also indicated that there was an outstanding misdemeanor warrant for his arrest. Based upon the outstanding warrant, Officer Sargent placed respondent under arrest. While being handcuffed, respondent dropped a hand-rolled cigarette that the officers determined smelled of marijuana. Officers proceeded to search his car and discovered a bag of marijuana under the passenger's seat.

The State charged respondent with possession of marijuana. When the police notified the Justice Court that they had arrested him, the Justice Court discovered that the arrest warrant previously had been quashed and so advised the police. Respondent argued that because his arrest was based on a warrant that had been quashed 17 days prior to his arrest, the marijuana seized incident to the arrest should be suppressed as the fruit of an unlawful arrest. Respondent also argued that "[t]he `good faith' exception to the exclusionary rule [was] inapplicable . . . because it was police error, not judicial error, which caused the invalid arrest." App. 5.

At the suppression hearing, the Chief Clerk of the Justice Court testified that a Justice of the Peace had issued the arrest warrant on December 13, 1990, because respondent had failed to appear to answer for several traffic violations. On December 19, 1990, respondent appeared before a pro tem Justice of the Peace who entered a notation in respondent's file to "quash warrant." Id., at 13.

The Chief Clerk also testified regarding the standard court procedure for quashing a warrant. Under that procedure a justice court clerk calls and informs the warrant section of the Sheriff's Office when a warrant has been quashed. The Sheriff's Office then removes the warrant from its computer records. After calling the Sheriff's Office, the clerk makes a note in the individual's file indicating the clerk who made the phone call and the person at the Sheriff's Office to whom the clerk spoke. The Chief Clerk testified that there was no indication in respondent's file that a clerk had called and notified the Sheriff's Office that his arrest warrant had been quashed. A records clerk from the Sheriff's Office also testified that the Sheriff's Office had no record of a telephone call informing it that respondent's arrest warrant had been quashed. Id., at 42–43.

At the close of testimony, respondent argued that the evidence obtained as a result of the arrest should be suppressed because "the purposes of the exclusionary rule would be served here by making the clerks for the court, or the clerk for the Sheriff's office, whoever is responsible for this mistake, to be more careful about making sure that warrants are removed from the records." Id., at 47. The trial court granted the motion to suppress because it concluded that the State had been at fault for failing to quash the warrant. Presumably because it could find no "distinction between State action, whether it happens to be the police department or not," id., at 52, the trial court made no factual finding as to whether the Justice Court or Sheriff's Office was responsible for the continued presence of the quashed warrant in the police records.

A divided panel of the Arizona Court of Appeals reversed because it "believe[d] that the exclusionary rule [was] not intended to deter justice court employees or Sheriff's Office employees who are not directly associated with the arresting officers or the arresting officers' police department." 172 Ariz. 314, 317, 836 P. 2d 1024, 1027 (1992). Therefore, it concluded, "the purpose of the exclusionary rule would not be served by excluding the evidence obtained in this case." Ibid.

The Arizona Supreme Court reversed. 177 Ariz. 201, 866 P. 2d 869 (1994). The court rejected the "distinction drawn by the court of appeals . . . between clerical errors committed by law enforcement personnel and similar mistakes by court employees." Id., at 203, 866 P. 2d, at 871. The court predicted that application of the exclusionary rule would "hopefully serve to improve the efficiency of those who keep records in our criminal justice system." Id., at 204, 866 P. 2d, at 872. Finally, the Court concluded that "[e]ven assuming that deterrence is the principal reason for application of the exclusionary rule, we disagree with the court of appeals that such a purpose would not be served where carelessness by a court clerk results in an unlawful arrest." Ibid.

We granted certiorari to determine whether the exclusionary rule requires suppression of evidence seized incident to an arrest resulting from an inaccurate computer record, regardless of whether police personnel or court personnel were responsible for the record's continued presence in the police computer. 511 U. S. ___ (1994). We now reverse.

We first must consider whether we have jurisdiction to review the Arizona Supreme Court's decision. Respondent argues that we lack jurisdiction under 28 U. S. C. §1257 because the Arizona Supreme Court never passed upon the Fourth Amendment issue and instead based its decision on the Arizona good-faith statute, Ariz. Rev. Stat. Ann. §13–3925 (1993), an adequate and independent state ground. In the alternative, respondent asks that we remand to the Arizona Supreme Court for clarification.

In Michigan v. Long, 463 U. S. 1032 (1983), we adopted a standard for determining whether a state-court decision rested upon an adequate and independent state ground. When "a state court decision fairly appears to rest primarily on federal law, or to be interwoven with the federal law, and when the adequacy and independence of any possible state law ground is not clear from the face of the opinion, we will accept as the most reasonable explanation that the state court decided the case the way it did because it believed that federal law required it to do so." Id., at 1040–1041. We adopted this practice, in part, to obviate the "unsatisfactory and intrusive practice of requiring state courts to clarify their decisions to the satisfaction of this Court." Id., at 1041. We also concluded that this approach would "provide state judges with a clearer opportunity to develop state jurisprudence unimpeded by federal interference, and yet will preserve the integrity of federal law." Ibid.

Justice Ginsburg would overrule Michigan v. Long, supra, because she believes that the rule of that case "impedes the States' ability to serve as laboratories for testing solutions to novel legal problems." Post, at 2. The opinion in Long describes the 60-year history of the Court's differing approaches to the determination whether the judgment of the highest court of a State rested on federal or nonfederal grounds. 463 U. S., at 1038–1040. When we were in doubt, on some occasions we dismissed the writ of certiorari; on other occasions we vacated the judgment of the state court and remanded so that it might clarify the basis for its decision. See ibid. The latter approach did not always achieve the desired result and burdened the state courts with additional work. Ibid.

We believe that Michigan v. Long properly serves its purpose and should not be disturbed. Under it, state courts are absolutely free to interpret state constitutional provisions to accord greater protection to individual rights than do similar provisions of the United States Constitution. They also are free to serve as experimental laboratories, in the sense that Justice Brandeis used that term in his dissenting opinion in New State Ice Co. v. Liebmann, 285 U. S. 262, 311 (1932) (urging that the Court not impose federal constitutional restraints on the efforts of a State to "serve as a laboratory"). Under our decision today, the State of Arizona remains free to seek whatever solutions it chooses to problems of law enforcement posed by the advent of computerization. Indeed, it is freer to do so because it is disabused of its erroneous view of what the United States Constitution requires.

State courts, in appropriate cases, are not merely free to—they are bound to—interpret the United States Constitution. In doing so, they are not free from the final authority of this Court. This principle was enunciated in Cohens v. Virginia, 6 Wheat. 264 (1821), and presumably Justice Ginsburg does not quarrel with it. In Minnesota v. National Tea Co., 309 U. S. 551 (1940), we recognized that our authority as final arbiter of the United States Constitution could be eroded by a lack of clarity in state-court decisions.

"It is fundamental that state courts be left free and unfettered by us in interpreting their state constitutions. But it is equally important that ambiguous or obscure adjudications by state courts do not stand as barriers to a determination by this Court of the validity under the federal constitution of state action. Intelligent exercise of our appellate powers compels us to ask for the elimination of the obscurities and ambiguities from the opinions in such cases. . . . For no other course assures that important federal issues, such as have been argued here, will reach this Court for adjudication; that state courts will not be the final arbiters of important issues under the federal constitution; and that we will not encroach on the constitutional jurisdiction of the states." Id., at 557.

We therefore adhere to the standard adopted in Michigan v. Long, supra.

Applying that standard here, we conclude that we have jurisdiction. In reversing the Court of Appeals, the Arizona Supreme Court stated that "[w]hile it may be inappropriate to invoke the exclusionary rule where a magistrate has issued a facially valid warrant (a discretionary judicial function) based on an erroneous evaluation of the facts, the law, or both, Leon, 468 U. S. 897 . . . (1984), it is useful and proper to do so where negligent record keeping (a purely clerical function) results in an unlawful arrest." 177 Ariz., at 204, 866 P. 2d, at 872. Thus, the Arizona Supreme Court's decision to suppress the evidence was based squarely upon its interpretation of federal law. See ibid. Nor did it offer a plain statement that its references to federal law were "being used only for the purpose of guidance, and d[id] not themselves compel the result that [it] reached." Long, supra, at 1041.

The Fourth Amendment states that "[t]he right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures, shall not be violated, and no Warrants shall issue, but upon probable cause, supported by Oath or affirmation, and particularly describing the place to be searched, and the persons or things to be seized." U. S. Const. We have recognized, however, that the Fourth Amendment contains no provision expressly precluding the use of evidence obtained in violation of its commands. See United States v. Leon, 468 U. S. 897, 906 (1984). "The wrong condemned by the [Fourth] Amendment is `fully accomplished' by the unlawful search or seizure itself," ibid. (quoting United States v. Calandra, 414 U. S. 338, 354 (1974)), and the use of the fruits of a past unlawful search or seizure "`work[s] no new Fourth Amendment wrong,'" Leon, supra, at 906 (quoting Calandra, supra, at 354).

"The question whether the exclusionary rule's remedy is appropriate in a particular context has long been regarded as an issue separate from the question whether the Fourth Amendment rights of the party seeking to invoke the rule were violated by police conduct." Illinois v. Gates, 462 U. S. 213, 223 (1983); see also United States v. Havens, 446 U. S. 620, 627–628 (1980); Stone v. Powell, 428 U. S. 465, 486–487 (1976); Calandra, supra, at 348. The exclusionary rule operates as a judicially created remedy designed to safeguard against future violations of Fourth Amendment rights through the rule's general deterrent effect. Leon, supra, at 906; Calandra, supra, at 348. As with any remedial device, the rule's application has been restricted to those instances where its remedial objectives are thought most efficaciously served. Leon, supra, at 908; Calandra, supra, at 348. Where "the exclusionary rule does not result in appreciable deterrence, then, clearly, its use . . . is unwarranted." United States v. Janis, 428 U. S. 433, 454 (1976).

In Leon, we applied these principles to the context of a police search in which the officers had acted in objectively reasonable reliance on a search warrant, issued by a neutral and detached Magistrate, that later was determined to be invalid. 468 U. S., at 905. On the basis of three factors, we determined that there was no sound reason to apply the exclusionary rule as a means of deterring misconduct on the part of judicial officers who are responsible for issuing warrants. See Illinois v. Krull, 480 U. S. 340, 348 (1987) (analyzing Leon, supra). First, we noted that the exclusionary rule was historically designed "`to deter police misconduct rather than to punish the errors of judges and magistrates.'" Krull, supra, at 348 (quoting Leon, supra, at 916). Second, there was "`no evidence suggesting that judges and magistrates are inclined to ignore or subvert the Fourth Amendment or that lawlessness among these actors requires the application of the extreme sanction of exclusion.'" Krull, supra, at 348 (quoting Leon, supra, at 916). Third, and of greatest importance, there was no basis for believing that exclusion of evidence seized pursuant to a warrant would have a significant deterrent effect on the issuing judge or magistrate. Krull, supra, at 348.

The Leon Court then examined whether application of the exclusionary rule could be expected to alter the behavior of the law enforcement officers. We concluded:

"[W]here the officer's conduct is objectively reasonable, `excluding the evidence will not further the ends of the exclusionary rule in any appreciable way; for it is painfully apparent that . . . the officer is acting as a reasonable officer would and should act in similar circumstances. Excluding the evidence can in no way affect his future conduct unless it is to make him less willing to do his duty.'" Leon, supra, at 919–920 (quoting Stone v. Powell, supra, at 539–540 (White, J., dissenting)).

See also Massachusetts v. Sheppard, 468 U. S. 981, 990–991 (1984) ("[S]uppressing evidence because the judge failed to make all the necessary clerical corrections despite his assurances that such changes would be made will not serve the deterrent function that the exclusionary rule was designed to achieve"). Thus, we held that the "marginal or nonexistent benefits produced by suppressing evidence obtained in objectively reasonable reliance on a subsequently invalidated search warrant cannot justify the substantial costs of exclusion." Leon, supra, at 922.

Respondent relies on United States v. Hensley, 469 U. S. 221 (1985), and argues that the evidence seized incident to his arrest should be suppressed because he was the victim of a Fourth Amendment violation. Brief for Respondent 10–12, 21–22. In Hensley, the Court determined that evidence uncovered as a result of a Terry stop was admissible because the officers who made the stop acted in objectively reasonable reliance on a flyer that had been issued by officers of another police department who possessed a reasonable suspicion to justify a Terry stop. 469 U. S., at 231. Because the Hensley Court determined that there had been no Fourth Amendment violation, id., at 236, the Court never considered whether the seized evidence should have been excluded. Hensley does not contradict our earlier pronouncements that "[t]he question whether the exclusionary rule's remedy is appropriate in a particular context has long been regarded as an issue separate from the question whether the Fourth Amendment rights of the party seeking to invoke the rule were violated by police conduct." Gates, supra, at 223; see also Stone v. Powell, supra, at 486–487; Calandra, 414 U. S., at 348.	Respondent also argues that Whiteley v. Warden, Wyoming State Penitentiary, 401 U. S. 560 (1971), compels exclusion of the evidence. In Whiteley, the Court determined that the Fourth Amendment had been violated when police officers arrested Whiteley and recovered inculpatory evidence based upon a radio report that two suspects had been involved in two robberies. Id., at 568–569. Although the "police were entitled to act on the strength of the radio bulletin," the Court determined that there had been a Fourth Amendment violation because the initial complaint, upon which the arrest warrant and subsequent radio bulletin were based, was insufficient to support an independent judicial assessment of probable cause. Id., at 568. The Court concluded that "an otherwise illegal arrest cannot be insulated from challenge by the decision of the instigating officer to rely on fellow officers to make the arrest." Ibid. Because the "arrest violated [Whiteley's] constitutional rights under the Fourth and Fourteenth Amendments; the evidence secured as an incident thereto should have been excluded from his trial. Mapp v. Ohio, 367 U. S. 643 (1961)." Whiteley, supra, at 568–569.

Although Whiteley clearly retains relevance in determining whether police officers have violated the Fourth Amendment, see Hensley, supra, at 230–231, its precedential value regarding application of the exclusionary rule is dubious. In Whiteley, the Court treated identification of a Fourth Amendment violation as synonymous with application of the exclusionary rule to evidence secured incident to that violation. 401 U. S., at 568–569. Subsequent case law has rejected this reflexive application of the exclusionary rule. Cf. Krull, supra; Sheppard, supra; United States v. Leon, 468 U. S. 897 (1984); Calandra, supra. These later cases have emphasized that the issue of exclusion is separate from whether the Fourth Amendment has been violated, see e.g., Leon, supra, at 906, and exclusion is appropriate only if the remedial objectives of the rule are thought most efficaciously served, see Calandra, supra, at 348.

Our approach is consistent with the dissenting Justices' position in Illinois v. Krull, our only major case since Leon and Sheppard involving the good-faith exception to the exclusionary rule. In that case, the Court found that the good-faith exception applies when an officer conducts a search in objectively reasonable reliance on the constitutionality of a statute that subsequently is declared unconstitutional. Krull, 480 U. S., at 346. Even the dissenting Justices in Krull agreed that Leon provided the proper framework for analyzing whether the exclusionary rule applied; they simply thought that "application of Leon's stated rationales le[d] to a contrary result." 480 U. S., at 362 (O'Connor, J., dissenting). In sum, respondent does not persuade us to abandon the Leon framework.

Applying the reasoning of Leon to the facts of this case, we conclude that the decision of the Arizona Supreme Court must be reversed. The Arizona Supreme Court determined that it could not "support the distinction drawn . . . between clerical errors committed by law enforcement personnel and similar mistakes by court employees," 177 Ariz., at 203, 866 P. 2d, at 871, and that "even assuming . . . that responsibility for the error rested with the justice court, it does not follow that the exclusionary rule should be inapplicable to these facts," ibid.

This holding is contrary to the reasoning of Leon, supra; Massachusetts v. Sheppard, 480 U. S. 981 (1984); and, Krull, supra. If court employees were responsible for the erroneous computer record, the exclusion of evidence at trial would not sufficiently deter future errors so as to warrant such a severe sanction. First, as we noted in Leon, the exclusionary rule was historically designed as a means of deterring police misconduct, not mistakes by court employees. See Leon, supra, at 916; see also Krull, supra, at 350. Second, respondent offers no evidence that court employees are inclined to ignore or subvert the Fourth Amendment or that lawlessness among these actors requires application of the extreme sanction of exclusion. See Leon, supra, at 916, and n. 14; see also Krull, supra, at 350–351. To the contrary, the Chief Clerk of the Justice Court testified at the suppression hearing that this type of error occurred once every three or four years. App. 37.

Finally, and most important, there is no basis for believing that application of the exclusionary rule in these circumstances will have a significant effect on court employees responsible for informing the police that a warrant has been quashed. Because court clerks are not adjuncts to the law enforcement team engaged in the often competitive enterprise of ferreting out crime, see Johnson v. United States, 333 U. S. 10, 14 (1948), they have no stake in the outcome of particular criminal prosecutions. Cf. Leon, supra, at 917; Krull, supra, at 352. The threat of exclusion of evidence could not be expected to deter such individuals from failing to inform police officials that a warrant had been quashed. Cf. Leon, supra, at 917; Krull, supra, at 352.

If it were indeed a court clerk who was responsible for the erroneous entry on the police computer, application of the exclusionary rule also could not be expected to alter the behavior of the arresting officer. As the trial court in this case stated: "I think the police officer [was] bound to arrest. I think he would [have been] derelict in his duty if he failed to arrest." App. 51. Cf. Leon, supra, at 920 ("`Excluding the evidence can in no way affect [the officer's] future conduct unless it is to make him less willing to do his duty.'" quoting Stone v. Powell, 428 U. S., at 540 (White, J., dissenting)). The Chief Clerk of the Justice Court testified that this type of error occurred "on[c]e every three or four years." App. 37. In fact, once the court clerks discovered the error, they immediately corrected it, id., at 30, and then proceeded to search their files to make sure that no similar mistakes had occurred, id., at 37. There is no indication that the arresting officer was not acting objectively reasonably when he relied upon the police computer record. Application of the Leon framework supports a categorical exception to the exclusionary rule for clerical errors of court employees. See Leon, 468 U. S., at 916–922; Sheppard, supra, at 990–991.

The judgment of the Supreme Court of Arizona is therefore reversed, and the case is remanded to that court for proceedings not inconsistent with this opinion.

It is so ordered.