There are certain pillars of jurisprudence which, despite the erosive elements of time and progress, remain sacred. After more than a century of judicial dialogue the venerable M'Naghten Rule survives as the prevailing test to determine criminal responsibility. The rule states: "To establish a defense on the ground of insanity, it must be clearly proved that, at the time of the committing of the act, the party accused was labouring 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 that what he was doing was wrong."
Comments and Casenotes: To Kill a Mockingbird - Star Decisis and M'Naghten in Maryland, 26 Md. L. Rev. 143 (1966)