• The insanity defense is distinct from competency to stand trial. The latter deals with the defendant’s ability to understand what is happening at trial (as well as at pretrial hearings, etc.).

• Insanity is not the same as diminished capacity, the latter of which is a failure of proof defense.

• Under the M’Naghten test, a defendant may escape liability if he “was labouring [sic] under such a defect of reason, from disease of the mind, as not to know the nature and quality of the act he was doing; or, if he did know it, that he did not know he was doing what was wrong.”

• According to the irresistible impulse test, a person is insane if he or she “acted from an irresistible and uncontrollable impulse.”

• The Model Penal Code “substantial capacity” test contains both cognitive and volitional components.

• The product test provides that “an accused is not criminally responsible if his unlawful act was the product of mental disease or defect.”

• Federal law provides an affirmative defense of insanity that emphasizes a “mental disease or defect.”
• Typically, a person who is found not guilty by reason of insanity (NGRI) is confined to an institution where that person can presumably be treated.

Questions:-

1. Explain the difference between diminished capacity and insanity.
2. Identify and define the different tests for insanity used throughout the United States.
3. Should the insanity defense be abolished? Why or why not?