Insanity defense

From Academic Kids

In a criminal trial, the insanity defense are possible defenses by excuse, via which a defendant may argue that they should not be held criminally liable for breaking the law, as they were mentally ill or mentally incompetent at the time of their allegedly "criminal" actions.

The insanity defense is available in most jurisdictions that respect human rights and have a rule of law, though the extent to which it can be applied may differ widely between jurisdictions.

This defense is based on a principle that punishment is only reasonable if the defendant is capable of both controlling their behavior and understanding that they have committed a "wrongful act". It is argued that if someone is suffering from a mental disorder so that they are not capable of knowing or choosing right from wrong, they should not be punished. A defendant making this argument might be said to be pleading "not guilty by reason of insanity" (NGRI).


Psychiatric treatment

Those found to have been not guilty by reason of insanity are generally then required to undergo psychiatric treatment; except in the case of temporary insanity (see below). Defendants found not guilty by reason of insanity are generally placed in a mental institution. Unlike defendants who are found guilty of a crime, they are not institutionalized for a fixed period, but rather they are held within the institution until authorities determine that they are no longer a threat. Authorities making this decision tend to be cautious; as a result, defendants can often spend more time there than they would have in prison (had they been convicted). In Foucha v. Louisiana (1992) the Supreme Court ruled that a person could not be held "indefinitely".

Psychosis and schizophrenia

In practice, a finding of "not guilty by reason of insanity" almost always requires that the defendant have been in a state of active psychosis (at the time the law was broken) and usually such findings involve a diagnosis of paranoid schizophrenia. The use of the insanity defense in cases of psychopathy is rare and almost uniformly unsuccessful.

Incompetency, intoxication, and mental illness

The concept of insanity is different from the concept of incompetency. Incompetency denotes the inability of a defendant to understand the charges against them and to participate in their defense, and relates to the defendant's state of mind at the time of trial. A trial cannot proceed if a defendant has been found incompetent, unless the defendant later becomes competent.

In the United States, a trial in which the insanity defense is invoked typically involves the testimony of psychiatrists which argue that the defendant is or is not insane. If there is agreement between the prosecution and defense that the defendant is insane then typically a jury trial is waived and a trial occurs in front of a judge in which evidence is presented and a judgment rendered. If there is disagreement between the prosecution and defense, each will typically present expert witnesses to a jury which will decide whose witnesses to believe.

The legal concept of insanity is different from the psychiatric concept of mental illness. Frequently, a person whose mental illness is not under dispute will be determined sane as the court will argue that despite a "mental illness" the defendant should still be held responsible; such a ruling is known as either a Guilty but Mentally Ill (GBMI) or a Guilty but Insane verdict. Michigan (1975) was the first state to pass a GBMI verdict. Sometimes a person without mental illness can be found to be insane; for example, a person who is acting under the influence of a drug that was involuntarily administered (though voluntary intoxication has been rejected by most jurisdictions as a defence to crime). (See: involuntary intoxication)

History of the insanity defense

The concept of defense by insanity has existed since ancient Greece and Rome. The first complete transcript of an insanity trial dates 1724. In Ford v. Wainwright (1975) the US Supreme Court ruled that insane prisoners cannot be executed.

One novel use of the insanity defense occurred in the case of Lee Boyd Malvo who plead not guilty by reason of insanity in the Beltway sniper shootings. Many legal experts believe that the purpose of raising the defense was not to gain an acquittal but to allow the defense to introduce otherwise inadmissible evidence about Malvo's upbringing, his relationship with John Allen Muhammad, and his mental state. This evidence was intended to gain the jury's sympathy so that they would not invoke the death penalty, and was successful at doing so.

Controversy Over the insanity defense

There are many different interpretations of "insane" and many different notions of how to deal with insane individuals.

In the US (1982), the insanity defense came under increasing criticism following the acquittal of John Hinckley, Jr., who attempted to assassinate President Reagan. Critics of the defense argue that it relies too much on opinion and/or "permits" behavior by one group which is forbidden to another. “If you commit a big crime then you are crazy, and the more heinous the crime, the crazier you must be. Therefore you are not responsible, and nothing is your fault”

Some opponents of the insanity defense, including Thomas Szasz, believe that psychiatry itself emerged as a way to justify mercy, of making persons "exceptional" and thus not deserving of the harsh punishment we would as a society wish to dole out to people who had extremely selfish or widely shared rationales for their actions. Since extreme selfishness ("self-absorption") or broadly shared resentments (e.g. envy of the rich, hatred of another ethnic group) are somewhat infectious behaviors, some argue that schizophrenia and other "mental illness" were defined into existence to protect those whose motives and behaviors were not so infectious, and whose offenses were thus unlikely to be repeated by others. The cost of this system of mercy, however, was to classify the psychiatrist and patient in an ongoing unequal-power relationship. See myth of mental illness and antipsychiatry).

It is also alleged that insanity as an excuse was introduced in the ancient Roman legal system. The Latin tribes held various religious beliefs and they considered the insane to be divinely blessed, and therefore believed that human jurisdiction could not reach them. Some modern critics claim that this precludes the insanity defense's validity in a modern secular state, as it violates the Constitutional doctrine of seperation of church and state.

The public tends to believe that the insanity defense is used more often than it actually is, possibly because insanity-defense cases tend to be of a high-profile nature.

Some US courts have begun to ban the use of the insanity defense and a 1994 Supreme Court ruling upheld the right of Montana to do so. Idaho and Utah have also banned this defense.

Rules of appreciation

In this section, we discuss various rules applied in United States jurisdiction with respect to insanity defenses.

The M'Naghten Rule

The M'Naghten Rule (England and Wales, 1843) state that a person " not guilty of a crime if, at the time of the crime, they either didn't know what they were doing, or didn't know that what they were doing was wrong." This rule is as of 2005 the one adopted in the majority of jurisdictions within the US.

The irresistible impulse

There is also an idea of an irresistible impulse, which argues that a person may have known an act was illegal; but, because of a mental impairment, they couldn't control their actions. In 1994, Lorena Bobbitt was found not guilty of the felony of "malicious wounding" (the equivalent of mayhem), when her defense argued that an irresistible impulse led her to cut off her husband's penis.

The Durham rule

The Durham Rule or "product test" was set forth by the United States Court of Appeals for the District of Columbia Circuit in 1954 and states that "... an accused is not criminally responsible if his unlawful act was the product of mental disease or defect". After the 1970s, US jurisdictions have tended to not recognize this argument as it places emphasis on "mental disease or defect" and thus on testimony by psychiatrists and is argued to be somewhat ambigious.

The Insanity Defense Reform Act (US)

The Insanity Defense Reform Act, enacted by Congress in 1984 in response to the verdict in the Hinckley trial, and codified at Title 18, U.S. Code, Section 17, states that a person accused of a crime can be adjudged not guilty by reason of insanity if "the defendant, as a result of a severe mental disease or defect, was unable to appreciate the nature and quality or the wrongfulness of his acts."

The Substantial Capacity Test

The Substantial Capacity Test was defined by the American Law Institute, in its Model Penal Code. This argues that insanity should be defined as a lack of substantial capacity to control one's behavior. Substantial capacity is defined as: "the mental capacity needed to understand the wrongfulness of [an] act, or to conform...behavior to" This is related to the McNaghten Rule and the idea of 'irresistible impulse'.

The Brawner rule

The Brawner Rule (1972) argues that insanity should be decided by a jury. Under this proposal, juries are allowed to decide the "insanity question" as they see fit.

Temporary insanity

The notion of temporary insanity argues that a defendant was insane, but is now sane. A defendant found to have been temporarily insane will often be released without any requirements of psychiatric treatment. This defense was first used by U.S. Congressman Daniel Sickles of New York in 1859 after he had killed his wife's lover, Philip Barton Key, but was most used during the 1940s and 1950s. Since then, it has not been as successful.

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