Murray v. United States, 487 U.S. 533 (1988), was a United States Supreme Court decision that created the modern "independent source doctrine" exception to the exclusionary rule.

The exclusionary rule makes most evidence gathered through violations of the Fourth Amendment to the United States Constitution inadmissible in criminal trials as "fruit of the poisonous tree".

"[1] The case arose out of the conviction of Michael F. Murray for conspiracy to possess and distribute illegal drugs.

In applying for the warrant, the agents did not mention their prior illegal entry.

The majority opinion agreed with the government that "the independent source doctrine applies to evidence initially discovered during, or as a consequence of, an unlawful search but later obtained independently from activities untainted by the initial illegality.