What does not guilty by reason of insanity mean?
In movies and on television shows, a standard legal defense for a criminal defendant is insanity or temporary insanity. We also hear about this from time to time in real life, of course, but it is not an especially common legal defense. To most of us, the legal reasoning behind this defense is fairly mysterious even though we’ve probably seen it played out dozens of times. On a typical lawyer show, the defense lawyer brings in a psychologist that says that the defendant should not be held accountable for his or her actions because he or she has a certain mental illness that interferes with his or her reasoning capacity. If the jury thinks the person actually does have this mental illness, it finds him or her not guilty. This raises a number of questions that most shows don’t answer very clearly: • Why does being mentally ill excuse somebody from criminal guilt? • How is a jury of regular people qualified to determine whether or not somebody is mentally ill? • What level of mental illne
