The ALI rule, or American Law Institute Model Penal Code rule, is a recommended rule for instructing juries how to find a defendant in a criminal trial is not guilty by reason of insanity. It broadened the M'Naghten rule of whether a defendant was so mentally ill they he is unable to "know" the nature and quality of her criminal act, or know its wrongfulness, to a question of whether he had "substantial capacity to appreciate the criminality of his conduct". It also added a volitional component as to whether defendant was lacking in "substantial capacity to conform his conduct to the law". It arose from the case of United States v. Brawner.
The ALI rule is:
References
ALI rule Wikipedia(Text) CC BY-SA