10 U.S.C. § 850a: Art. 50a. Defense of lack of mental responsibility

It is an affirmative defense in a trial by court-martial that, at the time of the commission of the acts constituting the offense, the accused, as a result of a severe mental disease or defect, was unable to appreciate the nature and quality or the wrongfulness of the acts. Mental disease or defect does not otherwise constitute a defense. The accused has the burden of proving the defense of lack of mental responsibility by clear and convincing evidence. guilty; not guilty; or not guilty only by reason of lack of mental responsibility. guilty; not guilty; or not guilty only by reason of lack of mental responsibility. a majority of the members of the court-martial present at the time the vote is taken determines that the defense of lack of mental responsibility has been established; or in the case of a court-martial composed of a military judge only, the military judge determines that the defense of lack of mental responsibility has been established.