Brief Fact Summary. Appellant was convicted of second-degree murder. The Court held a rehearing to determine the proper standard for the insanity test.
Synopsis of Rule of Law. A person is not responsible for criminal conduct if at the time of such conduct as a result of mental disease or defect, he lacked substantial capacity either to appreciate the criminality of his conduct or conform his conduct to the requirements of the law.
Issue. Whether there should be a new standard adopted with respect to the defense of insanity.
Held. The Court decided to accept the American Law Institute definition of insanity as defined below for trials after this date.
A person is not responsible for criminal conduct if at the time of such conduct as a result of mental disease or defect he lacks substantial capacity either to appreciate the criminality of his conduct or to conform his conduct to the requirements of the law.
A mental disease or defect includes any abnormal condition of the mind which substantially affects mental or emotional processes and substantially impairs behavior controls.
Dissent. The dissent concurred but dissented on the adoption of the new insanity test. Specifically, the dissent found fault with language that directed the jury to find that acquittal was necessary if the incapacity is substantial. The dissent argued that this left too much in a grey area and provided no real guidance to the jury. Thus, the jury might go back to relying solely on the testimony of experts.
Discussion. The Court ruled that the primary reason they were departing from the old test of insanity is that it put substantial dominance on the testimony of experts. The Court exhaustively examined the justification for the defense of insanity and the need to guide the jury with a specific framework for the insanity defense. The American Law Institute provided a better framework in the majority’s opinion because it took part of the reliance on experts away and focused on the acts and mental state of a defendant at the time he committed the acts constituting the crime.