There is universal agreement that it is a violation of due process as well as the nonconstitutional procedural law of virtually all jurisdictions to try a defendant who is mentally "incompetent." The procedural significance of the due process bar against trying or convicting an incompetent defendant is increased because of the trial judge's duty to inquire without request into a defendant's competency under certain circumstances. In Pate v. Robinson, defense counsel conceded at trial that Robinson shot and killed his common-law wife, but counsel claimed that Robinson was insane at the time of the shooting and raised the issue of his competence to stand trial. The trial court refused to conduct a hearing on the defendant's competence to stand trial. The U.S. Supreme Court ruled that Robinson was constitutionally entitled to a hearing on the issue of his competency to stand trial. The Court directed the district court to order Robinson discharged, after affording the State another opportunity to put Robinson to trial on its charges within a reasonable time. In Jackson v. Indiana, the U.S. Supreme Court held that a criminal defendant institutionalized solely on account of incompetency to stand trial cannot be held more than the reasonable period of time necessary to determine whether there is a substantial probability that competency to stand trial will be attained in the foreseeable future. At such time, the State must either institute the customary civil commitment proceeding required for any citizen or release the defendant. Case notes are provided.