Cleveland police went to Dollree Mapp’s home seeking a bombing suspect and gambling evidence. After initially being refused entry, officers later forced their way in, waving a paper they claimed was a warrant; no valid warrant was produced at trial. During the search, police found allegedly obscene books and pictures in a trunk, and Mapp was prosecuted under Ohio law for possessing them. She challenged the conviction on the ground that the evidence was obtained through an unconstitutional search and seizure.
Does the Fourteenth Amendment require state courts to exclude evidence obtained by state officers in violation of the Fourth Amendment?
The exclusionary rule, which bars the use of evidence obtained through unconstitutional searches and seizures, is part of the Fourth Amendment and is enforceable against the states through the Fourteenth Amendment. Evidence obtained in violation of the Constitution is inadmissible in state criminal prosecutions.
Yes. The Court held that evidence obtained by searches and seizures in violation of the Fourth Amendment is inadmissible in state courts.
The Court reasoned that the Fourth Amendment’s protection against unreasonable searches would be hollow without a remedy that meaningfully deters police misconduct. It rejected the prior approach that allowed states to admit illegally seized evidence, concluding that exclusion is an essential part of the constitutional guarantee. The Court relied on the logic of Weeks v. United States, 232 U.S. 383 (1914), and overruled Wolf v. Colorado, 338 U.S. 25 (1949), insofar as Wolf had declined to require the exclusionary rule in state prosecutions. Applying that principle, the search of Mapp’s home was unconstitutional, so the seized materials could not be used against her.
Justice Harlan, joined by Justices Frankfurter and Whittaker, argued that the Court should not have reached the broad Fourth Amendment question because the case had been litigated primarily on First Amendment grounds, and he disagreed with overruling Wolf v. Colorado, 338 U.S. 25 (1949), in this posture.
Mapp is a foundational incorporation decision that made the exclusionary rule binding on the states, dramatically reshaping state criminal procedure and police practices. It extended the federal rule recognized in Weeks v. United States, 232 U.S. 383 (1914), and expressly rejected Wolf v. Colorado, 338 U.S. 25 (1949), on the remedy question. The case became a cornerstone for later Fourth Amendment doctrine, including debates over the limits of exclusion in United States v. Leon, 468 U.S. 897 (1984), and related suppression-rule cases.
Weeks v. United States, 232 U.S. 383 (1914) |
Abstain |
Wolf v. Colorado, 338 U.S. 25 (1949) |
Verified |
United States v. Leon, 468 U.S. 897 (1984) |
Abstain |
Weeks v. United States, 232 U.S. 383 (1914) |
Abstain |
Wolf v. Colorado, 338 U.S. 25 (1949) |
Verified |
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