By Sir JAMES CRICHTON-BROWNE, M.D.
I CAN not pretend to summarize what has been written or said about insanity and crime during the last forty years, or a fourth of that time. All that I propose is to submit a few observations which have occurred to me on the following points: (1) on the insufficiency of the definition or test of insanity at present accepted and acted on in courts of law in this country, and on an amended test which would commend itself to medical experience; (2) on the value of expert testimony in establishing the existence and nature of insanity in courts of law; and (o) on a practical step toward the reconcilement of medical and legal differences of opinion on questions of insanity and crime.
What is the law of England with reference to insanity as an excuse for crime, and how far is that law reasonable and in accord with the conclusions of medical science? As to what the law is, there can not be much doubt, for every judgment delivered in cases in which the plea of insanity has been set up since 1843 has been founded on the answers then returned by the judges to the questions put to them by the House of Lords during the ground-swell of the McNaghten case. The gist of these answers runs: "That to establish a defense on the ground of insanity, it must be clearly proved that at the time of committing the act the accused was laboring 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." Now, it is obvious that under this ruling, if I may call it so, are included a large number of cases of insanity. Under it would stand excused the raving maniac who does not apprehend the nature or quality of any act, the idiot who is in the same predicament, the fatuous person who can not foresee the consequences of his acts, and the victim of delusions, when these are of such a character as would justify homicide were they beliefs entertained by a sane man. But it is, and always has been, equally obvious to medical men that this ruling excludes a considerable proportion of cases of insanity in which moral as distinguished from legal irresponsibility exists, and that it is faulty in founding the test of insanity on knowledge or an intellectual state while it ignores states of the emotions and will, which are always more influential on conduct than intellectual states, and bulk far more largely in insanity. The test of insanity which
- Abridged from a lecture delivered to the College of State Medicine.