Inevitable Discovery

Inevitable discovery is a doctrine in United States criminal procedure that permits illegally obtained evidence to be admitted at trial if the prosecution shows it would have been discovered through lawful means regardless. The Supreme Court formally adopted the doctrine in Nix v. Williams in 1984, a case in which police had violated the Sixth Amendment right to counsel of a defendant to learn where a murder victim was hidden, but the Court allowed the evidence because an ongoing search of the area would inevitably have found the body anyway. The prosecution must prove inevitable discovery only by a preponderance of the evidence, and the Court specifically declined to require any showing of police good faith, focusing instead on whether lawful investigation would eventually have reached the same evidence. The doctrine is meant to place police in the position they would have occupied had they followed proper procedure, balancing the deterrent purpose of the exclusionary rule against letting a guilty defendant escape justice over evidence that lawful methods would have produced regardless.