: THE INSANITY DEFENSE
• What are the legal standards for insanity?
Each state, and the District of Columbia, has its own statute setting out the standard for determining whether a defendant was legally insane, and therefore not responsible, at the time his crime was committed. In general, the standards fall into two categories.
About half of the states follow the "M'Naughten" rule, based on the 1843 British case of Daniel M'Naughten, a deranged woodcutter who attempted to assassinate the prime minister. He was acquitted, and the resulting standard is still used in 26 states in the U.S.: A defendant may be found not guilty by reason of insanity if "at the time of committing the act, 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 what he was doing was wrong." (emphasis added) This test is also commonly referred to as the "right/wrong" test.
Twenty-two jurisdictions use some variation of the Model Standard set out by the American Law Institute (A.L.I.) in 1962. Under the A.L.I. rule, a defendant is not held criminally responsible "if at the time of his conduct as a result of mental disease or defect he lacks substantial capacity either to appreciate the criminality (wrongfulness) of his conduct or to conform his conduct to the requirements of law." (emphasis added) The A.L.I. rule is generally considered to be less restrictive than the M'Naughten rule.
Some states that use the M'Naughten rule have modified it to include a provision for a defendant suffering under "an irresistible impulse" which prevents him from being able to stop himself from committing an act that he knows is wrong.
Three states -- Montana, Idaho, and Utah -- do not allow the insanity defense at all.
: See this chart showing the standards used by each jurisdiction.
• How often is the insanity defense invoked? In what kinds of cases? And how often does it succeed?
Although cases invoking the insanity defense often receive much media attention, the defense is actually not raised very often. Virtually all studies conclude that the insanity defense is raised in less than 1 percent of felony cases, and is successful in only a fraction of those1. The vast majority of those that are successful are the result of a plea agreement in which the prosecution and the defense agree to a not guilty by reason of insanity (NGRI) plea.
A major 1991 eight-state study commissioned by the National Institute of Mental Health found that less than 1 percent of county court cases involved the insanity defense, and that of those, only around one in four was successful. Ninety percent of the insanity defendants had been diagnosed with a mental illness. About half of the cases had been indicted for violent crimes; fifteen percent were murder cases.2
• What happens in states where there is no insanity defense?
Three states -- Montana, Idaho, and Utah -- do not allow the insanity defense. Defendants must still be found competent to stand trial, and they may introduce evidence of a mental disease or defect as evidence that they did not possess the requisite intent or state of mind (mens rea) to be found guilty.
• What is "guilty but mentally ill (GBMI)"?
Faced with the difficulty of cases such as Ralph Tortorici's, where a defendant has clearly committed the crimes in question but is obviously mentally ill, many states have adopted laws providing for a "guilty but mentally ill" plea or verdict. This does not eliminate the insanity defense; it is merely an alternative for defendants who are found to be mentally ill, but whose illness is not severe enough to relieve him of criminal responsibility.
A defendant who receives a GBMI verdict is sentenced in the same way as if he were found guilty. The court then determines whether and to what extent he requires treatment for mental illness. When, and if, the defendant is deemed "cured" of his mental illness, he is required to serve out the rest of his sentence, unlike an insanity-defense acquittee who would be released from psychiatric commitment once he is deemed to be no longer dangerous.
Proponents of the GBMI plea, including Cheryl Coleman, argue that it provides for necessary treatment of mentally ill defendants, while still ensuring that those defendants are punished for their crimes. They say that the GBMI verdict protects the public because mentally ill defendants won't be released if they are deemed no longer dangerous, as would a defendant who was acquitted by reason of insanity. On the other hand, they say, mentally ill defendants are guaranteed to receive the treatment they need, and suicides like Ralph Tortorici's would happen less often.
Critics, including the American Psychiatric Association, claim that the GBMI verdict takes away the hard choices that juries and judges are supposed to make: "While the 'guilty but mentally ill' category may seem to make juries' jobs easier, it compromises one of our criminal system's most important functions -- deciding, through its deliberations, how society defines responsibility. A 'guilty but mentally ill' plea absolves the judge or jury of this obligation."3
Another, practical criticism of the GBMI plea is that given the level of mental health resources in the countries' jails and prisons, it is unlikely that a defendant who receives a GBMI verdict will actually receive meaningful treatment while incarcerated. Mental health resources in prison are scarce, and because most statutes grant substantial discretion to the facility directors to provide a level of treatment that they determine is necessary, there is no guarantee that an inmate will receive adequate treatment.
In 2000, at least 20 states had enacted "guilty but mentally ill" provisions.
: For more on the debate over the GBMI plea, see this point-counterpoint article from Physicians Weekly.
• What is a bifurcated trial?
A few states allow for "bifurcated" trials for defendants invoking an insanity plea. The first phase deals with the crime itself and determines whether the defendant is guilty, without reference to insanity. If the defendant is found guilty, then he may raise an insanity defense in the second phase of the trial, which determines his sentence.