The Leon Good-faith Exception to the Probable Cause Requirement
The Leon good-faith exception to the probable cause requirement, was established by the Supreme Court in United States v. Leon, 468 U.S. 897 (1984). In United States v. Leon, the Court explained that because reasonable minds may differ as to whether a particular affidavit establishes probable cause, the preference for warrants is most appropriately effectuated by according great deference to a magistrate's determination.
The Court stated that the deference accorded to a magistrate's determination of probable cause "is not boundless . . . . It observed that reviewing courts will not defer to a warrant based on an affidavit that does not provide the magistrate with a substantial basis for determining the existence of probable cause; that sufficient information must be presented to the magistrate to allow that official to determine probable cause; and the magistrate's action cannot be a mere ratification of the bare conclusions of others. Id. at 915.
The Court emphasized that "the exclusionary rule was designed to deter police misconduct rather than to punish the errors of judges and magistrates." Id. at 916.
It said that "suppression of evidence obtained pursuant to a warrant should be ordered only on a case-by-case basis and only in those unusual cases in which exclusion will further the purposes of the exclusionary rule." Id. at 918.
In this regard, the Court questioned whether the exclusionary rule has a deterrent effect when the offending officers "acted in the objectively reasonable belief that their conduct did not violate the Fourth Amendment." Id.
As to the standard of reasonableness, the Court determined that it was an objective, rather than a subjective one, and required that "officers have a reasonable knowledge of what the law prohibits." Id. at 919 n.20.
Thus, where the officers' conduct is objectively reasonable, the Court said that excluding the evidence would not further the ends of the exclusionary rule in any appreciable way. This is particularly true, the Court said, when an officer acting with objective good faith has obtained a search warrant and acted within its scope. Id. at 920.
The Court explained that it is the magistrate's responsibility to establish whether the officer's allegations established probable cause, and accordingly an officer cannot be expected to question the magistrate's probable cause determination, or his judgment that the warrant is otherwise technically sufficient. Id. at 921.
Nevertheless, the Court said that because the officer's reliance must be objectively reasonable, there may be cases where the officer "will have no reasonable grounds for believing that the warrant was properly issued." Id. at 922-23.
The Court concluded that suppression was an appropriate remedy (1) if the magistrate, in issuing a warrant, "was misled by information in an affidavit that the affiant knew was false or would have known was false except for a reckless disregard of the truth," or (2) "in cases where the issuing magistrate wholly abandoned his judicial role . . . [so that] no reasonably well trained officer should rely on the warrant," or (3) in cases in which an officer would not "manifest objective good faith in relying on a warrant based on an affidavit so lacking in indicia of probable cause as to render official belief in its existence entirely unreasonable," or (4) in cases where "a warrant may be so facially deficient -- i.e., in failing to particularize the place to be searched or the things to be seized -- that the executing officers cannot reasonably presume [the warrant] to be valid." Id. at 923.
Thus, as summarized by the Court, 468 U.S. at 926, "in the absence of an allegation that the magistrate abandoned his detached and neutral role, suppression is appropriate only if the officers were dishonest or reckless in preparing their affidavit or could not have harbored an objectively reasonable belief in the existence of probable cause." Id. at 926.