What is the effect of a reversal of a conviction on a defendant's mental state?

subsequent competency determination. [Citation.] This is because a trial court's initial failure to hold a timely competency hearing is almost always rooted in a fundamental inattentiveness to the defendant's mental condition. The record in such cases will, therefore, seldom contain useful contemporaneous information regarding a defendant's mental state at the time of trial and his ability, at that time, to understand the nature of the proceedings and assist in his defense. For this reason, courts have declined to permit a retrospective competency hearing after reversing a conviction because of the failure to hold such a hearing originally. (See Pate v. Robinson (1966) 383 U.S. 375, 387 [86 S.Ct. 836, 15 L.Ed.2d 815] [noting the difficulty of retrospectively determining an accused's competence to stand trial].)