Key Concepts: Criminal Responsibility

Abstract

Mentally disordered persons occasionally do things for which we would ordinarily blame or even punish a non-disordered person. We often do not blame mentally disordered persons for these actions, however, because we regard mental disorders, at least in some circumstances, as an excuse from moral responsibility. For moral philosophy and the law, the challenge is to understand the specific circumstances under which a mental disorder should excuse an offender from responsibility for his or her actions. Because different types of psychopathology influence a person’s intentions and character in very different ways, judgments of responsibility crucially depend upon the specific nature of a mental disorder. They also depend on adequate understandings of concepts such as moral understanding, especially in the case of psychopathy, as well as an understanding of the reasons why mental disorders may excuse a person from responsibility.

The mentally ill often do things for which they are not responsible. This has long been recognized, by both morality and the law. But just which mentally ill persons should be excused, and under what circumstances, is an altogether more complicated affair.

In the Nicomachean Ethics, Aristotle distinguishes two types of involuntary actions, for which (by implication) a person might be excused from responsibility: those done in ignorance, and those that were compelled. Both excuses are variations on the theme of non-intention. If a person did not intend to act as he did—either because he did not know what he was doing, or because he could not help acting as he did—then he is not responsible for the action. Intention is also a key point for the law, which traditionally has said that for a crime to have been committed, it must be accompanied by evil intent, or mens rea (literally, “guilty mind.”)

The problem comes in saying how these distinctions play out for the mentally ill offender. The most widely used standards for determining criminal (legal) responsibility are based on the M’Naghten Rules, which excuse a person from responsibility for an act if, as a result of a mental disorder, he did not know the nature and quality of the act, or did not know that the act was wrong. This standard works nicely for the paradigmatic cases of mentally ill offenders; it would excuse, for example, the person with paranoid schizophrenia who strikes out violently at a person he falsely believes is threatening his life. However, it is unclear on several other points, the most famous of which relates to Aristotle’s excusing condition of compulsion. How should we regard those people, for example, whose psychosis impairs their ability to control their behavior, or whose mental disorders involve the control of their unusual desires, such as kleptomania, pyromania, pedophilia and voyeurism? Many of the latter such persons are aware of the nature and quality of what they desire to do, and they are aware that it is wrong, but they find great difficulty in resisting their desires.

One well-known effort to remedy this deficiency was the “irresistible impulse” test, which excused those persons who as a result of their condition had acted on desires that were irresistible. Yet the difference between an irresistible desire and a desire not resisted has proven notoriously difficult to distinguish, in practice as well as in theory.

Another chronic source of philosophical controversy is the question of responsibility for one’s character. In psychiatry, this debate surfaces most often with patients who have personality disorders. Ordinarily, since persons cannot control whether they incur a mental illness, they can be excused from responsibility for some actions they have taken while they were mentally ill. However, personality disorders are also (in some sense) beyond a person’s control, being the product of genetic inheritance and upbringing. This raises old issues of psychological determinism: if personality disorders are beyond a person’s control, is it just to hold that person responsible for the actions that result from them?

On the other hand, even if personality disorders are within the proper domain of psychiatry, they are obviously quite different from...