Which case established the "exclusionary rule"?

The case that established the "exclusionary rule" is Weeks v. United States. This landmark decision, decided in 1914, held that evidence obtained through illegal searches and seizures in violation of the Fourth Amendment could not be used in federal prosecutions. The ruling was pivotal in establishing a strong precedent aimed at protecting individuals' rights against unlawful governmental action, thereby promoting the integrity of the judicial system.

Weeks v. United States laid the groundwork for the exclusion of illegally obtained evidence, ensuring that law enforcement agencies adhere strictly to constitutional protections. This foundational principle has since been expanded to state courts through subsequent rulings, reinforcing the importance of the Fourth Amendment in safeguarding citizens' rights.

In contrast, other cases listed, such as Miranda v. Arizona, focused on the rights of individuals during custodial interrogations; Katz v. United States addressed the concept of reasonable expectation of privacy; and Terry v. Ohio dealt with stop-and-frisk procedures, but none of these established the exclusionary rule itself.