The exception to the exclusionary rule that permitted federal prosecutors to introduce at trial evidence obtained illegally by state law enforcement agents.

In Weeks v. United States[case]Weeks v. United States[Weeks v. United States] (1914), the Supreme Court articulated what became known as the exclusionary ruleExclusionary rule: Evidence obtained in violation of the Fourth Amendment was inadmissible in federal court. This decision, however, did not apply to state courts. In fact, thirty-five years later, in Wolf v. Colorado[case]Wolf v. Colorado[Wolf v. Colorado] (1949), the Court, while incorporating the Fourth Amendment into the Fourteenth Amendment, specifically rejected the notion that the exclusionary rule should be binding on the states. As a result, states were free to adopt or ignore the exclusionary rule.

This double standard gave rise to the silver platter doctrine. State law enforcement agents, often at the request of federal officers, conducted illegal seizures. The evidence obtained was then served up to federal authorities on a “silver platter” and was admissible in federal court because federal officers had not participated in its seizure. In Elkins v. United States[case]Elkins v. United States[Elkins v. United States] (1960), the Court abandoned this exception, claiming that it undermined federalism. In Mapp v. Ohio[case]Mapp v. Ohio[Mapp v. Ohio] (1961), the Court extended the exclusionary rule to state criminal prosecutions.

Exclusionary rule

Federalism

Fourth Amendment

Incorporation doctrine

Mapp v. Ohio

Weeks v. United States

Wolf v. Colorado