Boykin refers to the case Boykin v. Alabama, 395 U.S. 238 (1969) decided by the United States Supreme Court. This case is most often cited for the principle that guilty pleas are enforceable only if taken voluntarily and intelligently. Due process requires an affirmative showing that a defendant who pleads guilty to a criminal charge has been apprised of his constitutional rights and has knowingly and voluntarily waived those rights. Such waiver cannot be presumed and reversible error is presented when the record does not disclose that the defendant voluntarily and understandingly entered his pleas of guilty. In Boykin, the defendant was charged with common-law robbery. He pleaded guilty to the five indictments against him, and the trial court entered his plea of guilty.The jury sentenced defendant to death. On automatic appeal, the state supreme court affirmed the judgment, holding that a death sentence for robbery was not cruel and unusual punishment. On further appeal, court reversed defendant's conviction because the record contained no showing that his guilty plea was voluntary. The court held that an affirmative showing of voluntariness on the record was necessary in order to conclude that defendant had waived his constitutional rights.