Miranda v. Arizona
United States Supreme Court
384 U.S. 436 (1966)
Ernesto Miranda (defendant), who suffered from mental illness, confessed to kidnapping and rape after custodial police questioning in which he was never advised of his right to counsel, and his confession was admitted at trial resulting in his conviction, which the Arizona Supreme Court affirmed. Three consolidated companion cases involved similarly unwarned confessions: Vignera and Westover both confessed after extensive custodial interrogation without being told their rights and were likewise convicted, while the California Supreme Court reversed Stewart's conviction because the record didn't show whether he — a sixth-grade dropout — had been advised of his rights at all.
Whether, without certain hallmark warnings regarding the right to remain silent and the right to counsel, statements made during custodial interrogation are inadmissible at trial.