Contradictions inevitably emerge where the laws of man are confused with the laws of nature: The former can be broken; the latter cannot. These contradictions are what make the "insanity defense" in a trial like that of John Hinckley Jr. appear to be an affront to justice and common sense.
The concept of insanity is one of social expedience. Unfortunately for the law, which is a social apparatus, this concept is unsupportable by science, an apparatus for describing nature.
The rationale for the insanity defense is that certain people commit crimes because they are sick rather than evil. That these people ought to be treated humanely is a proper, subjective, value-laden prerogative of society. The primary premise behind this attitude is a cause-and-effect notion that personal responsibility for behavior is related to the laws of nature.
The idea that the universe operates by "effects" that are "caused" by one thing or another has no meaning in science. Gravity, for instance, is described by scientific theory, but it is not attributed to a "cause." So it is in all of science. Bertrand Russell said it well: "The reason why physics has ceased to look for causes is that, in fact, there are no such things."
Unhappily, the meaningless nature of the "cause-effect" idea is not widely appreciated, primarily because physicians and attorneys are trained in their technological areas but few are educated in the philosophy of science. Hence, the "cause-effect" pseudo-principle permeates not only the dogmatic canons of law but also the empirical technology commonly and incorrectly referred to as medical "science." (That psychiatrists "proving" insanity in court are enmeshed in this pseudo-principle simply shows that psychiatry can be pseudo-scientific.)
The "cause-effect" idea is a strictly narcissistic, human invention. It originates in early childhood when we haven't yet developed the capacity for abstract and critical thinking. This primitive, concrete notion that we can "cause" things to happen as an act of "will" does not change for most people as they grow, largely because it is reinforced by parental and, later, legal doctrines of personal responsibility.
Firmly in the grip of this idea, in 1843 the inventors of "insanity" developed a set of tests for individual responsibility called the "M'Naughten rules." They hold that a defendant is not responsible for his crimes if "he 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."
Despite the progress of psychiatric knowledge since 1843 and modifications of M'Naughten, the insanity defense has remained fundamentally unchanged--specifically the idea that insanity can be defined by law, not science.
Legislators know that they would be ridiculed if they tried to outlaw cancer or gravity. Yet, where psychiatry meets the law, equivalent absurdities are not only common, they are also promulgated proudly.
So by common law, statute and conventional practice, the participants in the criminal justice system have arbitrarily created a mythological mental state, insanity, and have appointed psychiatrists to be the "authorized experts" on this mythical state. But psychiatrists do not recognize insanity, so they try to adapt to it by referring to "psychosis," an empirically determined mental state that is unrelated to the "insane" state defined by the law.
Consider for a moment the tragic sequence by which murderers are found "not guilty by reason of insanity," treated psychiatrically, found sane again, released from custody and treatment, only to murder again. This chain of events is predictable when the difference between insanity and psychosis is understood:
Insanity, the opposite of sanity, is by definition a reversible state. Because it is refined by legal tests, whenever those tests are no longer positive, the person is defined as "sane." This concept does not recognize physical or psychological factors that might not be reversible.
Psychosis, on the other hand, is often found to be incurable; its symptoms can be relieved by drugs, but the symptom-free state lasts only as long as the drugs are administered. For example, a schizophrenic murderer typically hallucinates at the time of the crime, stops hallucinating with treatment, and resumes hallucinating when he stops taking medication.
Because it has no basis in empirical fact, the "insanity" concept occupies a place in folklore beside the unicorn and other products of imagination, and therefore is part of common mythology. Notice that, whereas there are experts in the mythology of unicorns, there are no experts in unicorns, because the unicorn is not available for study.
Consider a game in which two persons, each hired by opposing sides of the question, are asked to testify about the color of a unicorn. By the rules of the game, they are not permitted to challenge the existence of the unicorn, Would one expect nonsense to be the result? Of course. Any answer to a meaningless question is meaningless.
Calling on psychiatrists to participate in an insanity defense puts them in the impossible position of being experts on a mythical beast. Whatever their approach, they are accused of undermining a system of someone else's making that is based on humanitarian intentions but formulated and perpetuated by harmful delusion.
In order for society to meet both its humanitarian goal and its mandatory goal of defending itself, the delusion of "insanity" must be expunged. Lawmakers can help by formulating the concept of "guilty by reason of psychosis." Psychiatrists can help, and at the same time meet their goal of regaining their profession's integrity, by refusing the role of experts on "insanity."
Failure to eliminate this blight of delusion on our society is one crime for which there is no defense.
Donald E. Watson, MD taught and did research in biophysics and neurophysiology before entering the field of psychiatry. He has a private practice in Santa Ana, and teaches at UC Irvine Medical School.