Certain forms of masked or psychic epilepsy constitute the most puzzling problem that the expert in nervous and mental disease has to deal with where criminal acts are performed, apparently without sufficient motive, and yet where the limits of responsibility must if possible be determined. It is easy to dismiss these cases and to consider that because a certain amount of intelligence has been displayed in the performance of the act, and because the patient ordinarily understands perfectly the distinction between good and evil. { 253} that therefore the will must have been entirely free in the accomplishment of the criminal action and the intellect must have understood what it was doing. As yet the general public refuses to take the standpoint of the expert in mental diseases in many of these cases; and only when clergymen also shall come to a realisation of the pathological elements undermining free will in these cases, that justice will be properly tempered, not by unworthy or misplaced charity, but by the mercy which, knowing all, has learned duly to appreciate what is and what is not criminal.
Epilepsy, in certain of its obscurer forms, is responsible for many conditions in which there is a sudden access of insane excitement of a violent, often very impulsive, character, though sometimes of very short duration. During this state the patient is practically irresponsible, and yet he may have sufficient control over his actions to enable him to work serious harm. Such a stage of excitement may last not more than an hour or two; usually all trace of it passes off in a day or two; before and after it the patient may be in perfectly sound sense and in apparently good health. One of our best authorities here in America, Berkley, in his treatise on _Mental Diseases_, gives the following striking opinion on this subject.
"The subject of masked epilepsy and the consequent mania is replete with interest to the physician and the jurist, since such patients are prone to impulsive acts of violence and automatic states in which the most complicated, but entirely unconscious, actions and crimes may be carried out without premeditation on the part of the sufferer, being also out of all accord with his character during his intervals of mental health. Besides the irritability, impulsiveness is an equally characteristic feature. No form of insanity more frequently gives rise to assaults and murder than epilepsy, and in no form of alienation is the physician so frequently called to the witness stand to determine the responsibility of the criminal."