Potter Stewart

“ We conclude that where a codefendant takes the stand in his own defense, denies making an alleged out-of-court statement implicating the defendant, and proceeds to testify favorably to the defendant concerning the underlying facts, the defendant has been denied no rights protected by the Sixth and Fourteenth Amendments. ”

“ We held that where the jury hears the codefendant's confession implicating the defendant, the codefendant becomes in substance, if not in form, a 'witness' against the defendant. The defendant must constitutionally have an opportunity to 'confront' such a witness. ”

“ Runnels' out-of-court confession implicating the respondent was hearsay as to the latter, and therefore inadmissible against him under state evidence law. The trial judge so ruled, and instructed the jury that it must not consider any part of the statement in deciding whether or not the respondent was guilty. In Bruton, however, we held that, quite apart from the law of evidence, such a cautionary instruction to the jury is not an adequate protection for the defendant where the codefendant does not take the witness stand. ”