18 U.S.C. § 17 : US Code - Section 17: Insanity defense

Search 18 U.S.C. § 17 : US Code - Section 17: Insanity defense

(a) Affirmative Defense. - It is an affirmative defense to a
prosecution under any Federal statute that, at the time of the
commission of the acts constituting the offense, the defendant, as
a result of a severe mental disease or defect, was unable to
appreciate the nature and quality or the wrongfulness of his acts.
Mental disease or defect does not otherwise constitute a defense.
(b) Burden of Proof. - The defendant has the burden of proving
the defense of insanity by clear and convincing evidence.