In which of the following U.S. Supreme Court decisions was the exclusionary rule developed?

The development of the exclusionary rule in U.S. law is primarily attributed to Weeks v. U.S. In this landmark case, the Supreme Court held that evidence obtained through illegal searches and seizures by federal law enforcement cannot be used against a defendant in a federal prosecution. This established a crucial precedent for the protection of Fourth Amendment rights, which guard against unreasonable searches and seizures.

The significance of this ruling cannot be overstated, as it laid the foundation for the exclusionary rule, emphasizing the principle that the government must follow the law when gathering evidence. Subsequent cases, including Mapp v. Ohio, expanded the application of the exclusionary rule to state courts, but Weeks v. U.S. was fundamentally the genesis of this legal doctrine that aims to deter unlawful police conduct and uphold the integrity of the judicial system.