The Supreme Court ruled that the Fourth Amendment did not prohibit the admission of criminal evidence obtained from a search conducted pursuant to a warrant issued by a neutral and detached magistrate even if the warrant was ultimately found invalid through no fault of the police officers conducting the search.
Based on an affidavit referring to a confidential informant and various police observations, a state judge issued a search warrant authorizing police officers to search the residences of Alberto Leon and two other suspects. In the ensuing search, the police found large quantities of illegal drugs. At the trial, however, the court determined that the affidavit was insufficient to establish probable cause, and the evidence was thrown out.
By a 6-3 vote, the Supreme Court adopted the good faith exception, which stipulated that the exclusionary rule would not apply when the police were acting from an “objectively reasonable” belief that a search warrant is valid, even if the warrant later proves to be defective. Justice Byron R. White’s
Although the Leon ruling was rather narrow, the Court subsequently extended the conditions for applying the good faith exception to the exclusionary rule. In Illinois v. Krull
Mapp v. Ohio
Search warrant requirement