Which case established the "exclusionary rule"?

The case that established the "exclusionary rule" is Weeks v. United States. This rule is a legal principle that prohibits the use of evidence obtained in violation of a person's constitutional rights, particularly the Fourth Amendment, which protects against unreasonable searches and seizures. In Weeks v. United States, the Supreme Court ruled that evidence obtained through an illegal search and seizure by federal agents could not be used in federal court. This landmark decision set a precedent for excluding improperly obtained evidence, reinforcing the importance of adhering to constitutional protections in the criminal justice system.

The other cases listed, such as Katz v. United States and Miranda v. Arizona, are significant but pertain to different legal principles. Katz v. United States expanded the interpretation of the Fourth Amendment concerning electronic surveillance, while Miranda v. Arizona established the requirement for informing suspects of their rights during custodial interrogation. Terry v. Ohio established the standard for stop-and-frisk procedures, which also relates to the Fourth Amendment but does not address the exclusionary rule itself.