ssible to prove capacity of reason or will, but to even test such abstracts seems absurd. Additionally, the term "substantial capacity" lies question in that it is an abstract impossible to define. INSANITY: HOW IT IS ESTABLISHEDThe meaning of insanity is the legal definition as put forth in a rule such as the M'naghten Rule or whatever school of thought is in use on any given day. The legal test is applied in an adversary system which pitches lawyer against psychiatrist and psychiatrist against psychiatrist. Because of this, the psychiatrist is often perceived not as a scientist but a partisan for the side which is paying for his testimony (Jeffery, 1985;56). The major problem in this case being that the use of a neutral expert is impossible to implement. In the end the determination of insanity is a layman's decision since it is the jury which ultimately decides whether the defendant is sane or insane. This of course is ludicrous since professional scientists cannot agree on the meaning of mental illness. How can a layman make such a decision especially after listening to contradictory testimony which is manipulated by opposing lawyers. I believe that the major problem that we can point out here is in the futility of asking psychiatrists to testify in terms of legal concepts of insanity. The psychiatrist finds himself in a double bind: he has no medical definition of mental illness and he must answer questions from lawyers concerning legal insanity, right and wrong, and irresistible impulses. As stated by Packer: "The insanity defense cannot tolerate psychiatric testimony since the ethical foundations of the criminal law are rooted in beliefs about human rationality, deterribility, and free will. These are articles of moral faith rather than scientific fact." MENTAL ILLNESS AND CRIMINAL BEHAVIORIn the insanity defense we have no variable independent of the criminal behavior we are studying. Insanity refers to a class of behaviors know...
