This is the 2007 version. Click here for the 2017 chapter 14 table of contents.

Competence and Culpability

English common law is the starting point of much American law. English common law holds that a defendant cannot be tried unless that person is present and able to participate in the defense. In other words, people cannot be tried "in absentia" (in their own absence). This doctrine has been extended to people who are mentally "not there." They cannot be tried until they regain enough of their senses or intellect to help represent themselves at a trial. This is the issue known as competency to stand trial.

When is a person not competent to stand trial?

What are some other competency issues?

The issue of competence goes beyond competency to stand trial. Competence includes the ability to make decisions about your own life. Is a teenager competent to decide where to live? Normally you cannot move out of your home against your parents' wishes before you are 18. But, in a specific case, a psychologist might argue that your home situation was intolerable and your judgment was good, and the court might allow you to leave.

Most juveniles can be committed to a treatment center against their will, if parents think they need treatment, because juveniles are not competent to make such decisions under the law. Similarly, old people can be sent to a nursing home despite their protests, if they are judged to be mentally incompetent. A will is not legal unless the person who signs it is "of sound mind." In each case, a psychiatrist or psychologist may be asked to file a brief (written paper) with the court, evaluating a person's clarity of mind and decision-making ability.

The rules of criminal law force a judge or jury to make inferences about mental states such as knowledge, planning, and intention. Suppose you came out of class and found that your car had blown up for no apparent reason, and worse yet, somebody standing nearby had been badly injured in the explosion. If an investigation failed to reveal a cause of the explosion, you could not be charged with a crime. No reasonable person would expect that a car would suddenly blow up for no reason, and there would be no reason to blame you for it.

What is culpability? How is it a psychological judgment?

If, however, the car blew up because of your negligence (for example, because you left the gas cap off) you might be sued. If the car blew up because you gave some people gasoline and told them to wash tar off your fender with it, and somebody died in the resulting explosion, you could be charged with manslaughter: an irresponsible action that results in somebody's death. If you planned it and did it on purpose, you could be charged with murder. This is the issue of culpability or moral responsibility. Culpability implies agency (the ability to act), responsibility (the ability to determine what is appropriate and reasonable) and free will (the ability to decide what to do), all of which are inferred psychological states.

Manslaughter itself is commonly broken down into two categories: voluntary manslaughter involves intent but not a preplanning process (malice aforethought) so it is a category used for killings done "in the heat of the moment," rather than planned out ahead of time. Involuntary manslaughter lacks intent but shows irresponsibility; it is used for deaths caused by negligence, drunkenness, or wanton disregard of safety. Voluntary manslaughter involves less culpability than murder, in the eyes of the law, and is likely to result in a shorter sentence. In short, a person's mental state, degree of knowledge, planning, and responsibility, are extremely relevant to criminal law.

Why might an insane person be found not guilty despite committing a crime?

Sometimes an insane person does not exhibit mens rea—-the intention to commit an act—in a particular case. Therefore such a person cannot be found guilty in systems based on English law, like the system in the United States.

The insanity defense is one of the most controversial parts of United States law. If the court finds that a person was incapable of foreseeing the results of an action, then the intent to commit a crime is absent and the person cannot be found guilty. However, the verdict "not guilty by reason of insanity" sounds like a convenient way to avoid punishment. For this reason, judges and juries are suspicious of any attempt to use the insanity defense, and the insanity defense does not usually succeed.

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