Petitioner was convicted of burglary by a Louisiana court and his conviction was affirmed by the highest state court. Thereafter, in Mapp v. Ohio, 367 U.S. 643, this Court held that evidence illegally seized is inadmissible in a state criminal trial, and petitioner applied for a writ of habeas corpus. The writ was denied by the federal District Court and by the Court of Appeals, which found the searches of petitioners person and property illegal but held that the Mapp exclusionary rule was not retrospective. Held: The exclusionary rule announced in Mapp does not apply to state court convictions which had become final before its rendition. Pp. 622-640.

(a) The effect of a subsequent ruling of invalidity on prior final judgments when collaterally attacked is not automatic retroactive invalidity but depends upon a consideration of particular relations and conduct, or rights claimed to have become vested, of status, of prior determinations deemed to have finality, and of public policy in the light of the nature of the statute and its previous application. Chico