Supreme Court Refuses to Apply Exclusionary Rule to the States
The Supreme Court, in Wolf v. Colorado, held that the Fourteenth Amendment incorporated the protections of the Fourth Amendment and applied them to the states — but the Court refused to apply the Exclusionary Rule as a remedy for violations of the Fourth Amendment. The Exclusionary Rule prohibits police and prosecutors from using illegally seized evidence against a criminal defendant. The effect of the rule is to require the police to conduct searches in a lawful manner that complies with the Fourth Amendment. Civil libertarians regard the exclusionary rule as an important police accountability mechanism.
The Court had applied the rule in federal cases in Weeks v. United States on February 24, 1914. In Wolf, however, the Court refused to extend it to the states. The Court reversed itself in Mapp v. Ohio, and applied it to state criminal proceedings, on June 19, 1961.
Read: Carolyn Long, Mapp v. Ohio: Guarding Against Unreasonable Searches and Seizures (2006)
Learn about the history of the Mapp decision and the Exclusionary Rule: https://www.aclu.org/criminal-law-reform/aclu-history-mapp-v-ohio
Learn more: Stephen Schulhofer, More Essential Than Ever: The Fourth Amendment in the Twenty-First Century (2012)