The insanity defense gets a lot of attention for the role it has played in past high profile legal cases as well as for how often it gets featured in movies and television legal dramas. The truth of the matter is, however, that the insanity defense is not often raised and even less often successfully raised. In fact, various statistical analyses show that just about one percent of all U.S. felony cases involve the use of the insanity defense. Furthermore, the defense is only successfully raised in about 30 cases each year. We are here to clear up a few of the common public misconceptions about the insanity defense.
The Key Points of an Insanity Defense
When successfully asserted, the insanity defense demonstrates that the defendant was insane at the time the crime was committed and therefore should be held not guilty by reason of insanity. While those found not guilty by reason of insanity can avoid prison time, these individuals are not simply released from custody free and clear. Instead, a defendant found not guilty by reason of insanity is transferred into the custody of a psychiatric facility or mental health institution. In fact, these defendants will often stay in such a facility for much longer than they would have had they been convicted and sentenced to a period of incarceration.
The insanity defense is basically presented as an affirmative defense which provides that the defendant did in fact commit the act in question, but should not be held legally responsible by reason of insanity. Only certain states will permit assertion of the insanity defense. Texas is one of them. In these states, the defense team must prove that the defendant did not understand what they were doing, did not know right from wrong, acted on an uncontrollable impulse, or a combination of these different factors. Different jurisdictions will use different tests for legal insanity. These tests include:
- The M’Naghten Rule: Under this test, it must be demonstrated that the defendant did not understand his or her own actions. The defendant failed to differentiate right from wrong due to a mental condition. This is one of the most commonly employed tests and is often used in tandem with the irresistible impulse test.
- The Irresistible Impulse Test: Under this test, it must be demonstrated that, due to a mental condition, the defendant was unable to exercise adequate impulse control and this led to the criminal act.
- The Durham Rule: Under this test, it must be demonstrated that the defendant committed the criminal act because of his or her mental disease or mental defect. Most jurisdictions find this test to be overly broad and it is currently only used in New Hampshire.
- The Model Penal Code Test: Under this test, it must be demonstrated that a defendant failed to understand the criminal nature of the act or was unable to act within the confines of the law due to a diagnosed mental defect. This is another commonly employed test.
Some states do not allow use of the insanity defense. Others will instead permit a “guilty but insane” verdict. With a “guilty but insane” verdict, the defendant is often sentenced to institutionalization as opposed to imprisonment.