The "disease of the mind" required by the M'Naghten concept of legal insanity, means a psychosis and not some lesser illness or functional aberration.
Defendant killed her husband and was convicted of murder. Defendant maintained that she acted as a result of physical and mental abuse and was in a suicidal mindstate when she performed the act. The psychiatric report on defendant presented her as sane, but after the psychiatrists met and debated with defense counsel for several hours, they revised the report and changed their opinion as to her legal sanity on the night of the killing. During the jury trial, the prosecutor attacked the fact that expert witnesses changed their findings after conferring with defense counsel.
Did the defendant suffer from a "disease of the mind" under a defense of legal insanity that would justify the change in the report of the expert witnesses?
When the basis of the change in the experts' opinion was explored, it quickly appeared that the change was thoroughly consistent with honesty however mistaken it might be. In the minds of the witnesses, the change involved no alteration whatever in their medical findings. Rather it stemmed from an altered understanding of the law's concept of insanity. Specifically, the doctors originally understood that the "disease of the mind" required by the M'Naghten concept of legal insanity to which we adhere, means a psychosis and not some lesser illness or functional aberration. As the result of their pretrial debate with Mr. Saltzman, the doctors concluded they had had too narrow a view of M'Naghten and that the "anxiety neurosis" they had found did qualify as a "disease" within the legal rule, and hence when the anxiety reached a "panic" state, "meaning simply a severe disorganizing degree of anxiety," defendant did not know right from wrong and she did not know what she was doing was wrong because of that "disease."