Young College Girls Go Crazy

Most courts accept a major mental illness such as psychosis but will not accept the diagnosis of a personality disorder for the purposes of an insanity defense. The second question is whether the mental illness interfered with the defendant's ability to distinguish right from wrong. That is, did the defendant know that the alleged behavior was against the law at the time the offense was committed.
Additionally, some jurisdictions add the question of whether or not the defendant was in control of their behavior at the time of the offense. For example, if the defendant was compelled by some aspect of their mental illness to commit the illegal act, the defendant could be evaluated as not in control of their behavior at the time of the offense.
The forensic mental health specialists submit their evaluations to the court. Since the question of sanity or insanity is a legal question and not a medical one, the judge and or jury will make the final decision regarding the defendant's status regarding an insanity defense.
In most jurisdictions within the United States, if the insanity plea is accepted, the defendant is committed to a psychiatric institution for at least 60 days for further evaluation, and then reevaluated at least yearly after that.