Battalino v. People

In support of this assignment counsel relies particularly on Ingles v. People, 92 Colo. 518, 22 P.2d 1109. Our statute provides that if one of the defenses interposed by one charged with a criminal offense be insanity, said defense must be pleaded orally as a specification to the plea of not guilty. The question there posed was whether evidence of insanity offered, not for the purpose of defense, but for the purpose of mitigation only, was within the restriction of the statute, and we held that where a defendant chooses not to interpose a plea of not guilty by reason of insanity, but to stand upon the general plea of not guilty, he may not claim irresponsibility by reason of insanity and demand an acquittal on that ground, but that he is entitled to introduce evidence of insanity or mental derangement short of insanity, for the purpose, not of seeking an acquittal, but of reducing the grade of the crime from murder of the first degree to murder of the second degree.