Insanity: An Excerpt

Charles Patrick Ewing, Ph.D., J.D., is a forensic psychologist and attorney, as well as a SUNY Distinguished Service Professor at the State University of New York, University of Buffalo School of Law. His book, Insanity: Murder, Madness, and the Law, looks at ten of the most influential murder cases in which defendants have claimed insanity, taking the reader into the minds of some of the most incomprehensible murderers of our age. In the excerpt below we learn a little about about how “insanity” is defined by our legal systems.

Evolution of Legal Standards

The question of how criminal law should deal with mentally ill offenders has provoked controversy for centuries. As early as the 14th century, English law recognized that it was morally improper to punish a person whose mentality did not allow him to understand the difference between “good and evil.” By 1724, the courts had developed a standard of “insanity” that forbade criminal punishment of “a mad man…a man that is totally deprived of his understanding and memory, and doth not know what he is doing, no more than a brute or a wild beast.”

Modern insanity law, however, dates most directly to M’Naghten’s Case, an 1843 English decision of the Supreme Court of Judicature. Daniel M’Naghten had shot and killed Edward Drummond, mistakenly believing Drummond was Prime Minister Robert Peel. M’Naghten was found not guilty by reason of insanity, the queen was infuriated, and the House of Lords asked the court to clarify the law. In what has come to be known as the M’Naghten standard or test of insanity, the court directed that “the jurors ought to be told in all cases that ever man is to be presumed to be sane, and to possess a sufficient degree of reason to be responsible for his crimes, until the contrary be proved to their satisfaction; and that to establish a defense on the ground of insanity, it must be clearly proven that, at the time of the committing of the act, the party accused 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.” The two “prongs” of the M’Naghten standard – (1) inability to know the nature and quality of the act and (2) inability to know that the act was wrong – respectively deal with what have been referred to as cognitive incapacity and moral incapacity.

The M’Naghten standard, like the insanity defense more generally, has proven controversial but enduring. More than 165 years later, this test (or some variation of it) is still the law in the majority of American jurisdictions.

American reform of the insanity defense resulted in several alternatives to M’Naghten, including the “irresistible impulse” and “product” tests. Numerous 19th-century courts, including the U.S. Supreme Court, recognized that insanity included the inability to control one’s actions, despite knowing that such actions were wrong. Thus, under the “irresistible impulse” standard an accused was insane if found, by reason of mental illness, “unable to adhere to the right even though he knew the act was wrong.” A handful of other courts adopted a test asking simply whether the defendant’s criminal act was the “product” of a mental disease or defect. The “irresistible impulse” and “product” standard both reflected a concern for the defendant’s volitional capacity. Both these standards have largely been abandoned or incorporated into other insanity tests.

In 1962, the American Law Institute (ALI), an influential group of judges, lawyers, and law professors, posited a new insanity test, which was made part of the ALI’s Model Penal Code, a draft of recommended criminal laws. The ALI standard, which has become the major rival of M’Naghten, and the “irresistible impulse” standard. Under the ALI’s Model Penal Code, “a person is not responsible for criminal conduct if at the time of such conduct as a result of a mental disease or defect he lacks substantial capacity either to appreciate the criminality of his conduct or to conform his conduct to the requirements of the law.” The ALI definition of insanity also includes the caveat that “the terms ‘mental disease or defect’ do not include an abnormality manifested only by repeated criminal or otherwise antisocial conduct.”

Under the ALI formulation, a defendant may be found guilty by reason of insanity if lacking either cognitive or volitional capacity…

The next round of major changes to the law of insanity occurred in the United States after the trial of John W. Hinckley, Jr., in 1982, probably the most highly publicized insanity trial in history. In 1981, Hinckley, an apparently mentally ill drifter and son of wealthy parents, shot and nearly killed Ronald Reagan, the president of the United States…Charged with attempted murder, Hinckley pleaded insanity.

Hinckley’s defense was tried under then-existing federal law, which essentially paralleled the ALI insanity standard. At the time, the prosecution had the burden of proving beyond a reasonable doubt that the would-be-presidential assassin was sane…a jury deliberated only 3 days before finding Hinckley not guilty by reason of insanity.

The jury’s verdict, though not unreasonable given the law, the burden of proof, and the testimony presented by the defense experts in the case, touched off a firestorm of controversy that reverberated through the halls of Congress and state legislatures across the land.

In the wake of the Hinckley verdict, Congress narrowed the substantive federal insanity defense by deleting reference to volitional incapacity and by qualifying the nature of the required mental disease or defect. Under the Federal Insanity Defense Reform Act of 1984, “It is an affirmative defense to a prosecution under any Federal statute that, at the time of the commission of the acts constituting the offense, the defendant as a result of serious mental disease or defect, was unable to appreciate the nature and quality or wrongfulness of his acts. Mental disease or defect does not otherwise constitute a defense.” The amended federal insanity law also provided that “[t]he defendant has the burden of proving the defense of insanity by clear and convincing evidence.”

As part of the same legislation, Congress also amended the Federal Rules of Evidence…The following language was added to Federal Rule of Evidence 704: “No expert witness testifying with respect to the mental state or condition of a defendant in a criminal case may state an opinion or inference as to whether the defendant did or did not have the mental state or condition constituting an element of the crime charged or of a defense thereto. Such ultimate issues are matters for the trier of fact along.”

Although the Federal Insanity Reform Act was the most visible symbolic response to the Hinckley verdict and its critics, numerous state legislatures also responded to the controversial judgment. A dozen states supplemented their insanity laws by adopting a separate standard of “guilty by mentally ill,” under which a mentally ill defendant could be convicted and provided treatment while still subject to criminal punishment. Sixteen states shifted the burden of proof on insanity from the prosecution to the defendant. Seven states narrowed their substantive insanity standards, whereas three enacted legislation abolishing the insanity defense. Finally, half the states responded to the Hinckley verdict by making it more difficult for those acquitted by reason of insanity to be released from confinement following treatment…