Insanity and the Insanity Defense

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A defendant's legal responsibility for his or her criminal conduct is a controversial issue that continually draws public attention, particularly after highly publicized crimes. The insanity defense relates to the defendant's mental condition at the time of the crime rather than at the time of the trial. The latter issue, which is discussed as the defendant's competency to stand trial, is not the subject of this entry. The insanity defense deals with the criminal competency of an individual at a time in the past rather than at the time of the trial and sentencing.

Legal insanity is by definition a legal issue and should be distinguished from clinical insanity, which is not a term that is recognized by mental health professionals. The term temporary insanity sometimes is used by the general public to refer to a brief episode of mental illness and abnormal behavior that was present only at the time of the offense rather than before or after it. Legal insanity, however, is always temporary in the sense that it refers only to the defendant's behavior at the precise time of the alleged offense.

The insanity defense represents a special defense to a criminal offense. Although the prosecution generally has the responsibility of proving the defendant guilty beyond a reasonable doubt, a defendant is legally entitled to raise defenses to the charge, whether self-defense, alibi, misidentification, insanity, or another defense.

The insanity defense is one of many issues subsumed under the rubric of criminal responsibility. Although this entry reviews several of the important issues related to the special defense of insanity, it excludes several related issues, such as diminished mental capacity, diminished responsibility, guilty but mentally ill, and the sentencing of a mentally ill defendant after conviction.

There are public misperceptions about the insanity defense. That defense is used infrequently in criminal trials in the United States and is rarely successful. Empirical research has revealed that it is introduced in less than 1 percent of felony trials and is successful in fewer than onequarter of those trials. Many insanity acquittals occur through a stipulation between the prosecution and the defense rather than as a result of a contested trial. There is substantial variation among the states in the use and success of the insanity defense, with some states having more than seventy-five acquittals each year and many others having fewer than five. After acquittal insanity acquittees can remain hospitalized longer than they would have been imprisoned if they had been convicted of the same criminal offense and incarcerated. Generally, the public is not sympathetic to defendants who use the insanity defense for serious violent crimes except in cases of infanticide by severely depressed or mentally ill women.

Purpose of the Insanity Defense

The contemporary insanity defense had its origins more than 2,500 years ago, when it was recognized that certain categories of individuals, such as children, the mentally ill, and the developmentally disabled, could not be considered to be at fault for their offenses. A twentieth-century judge in the United States, David Bazelon, noted in the 1954 court decision Durham v. United States, "Our collective conscience does not allow punishment where it cannot impose blame." Generally, however, the criminal law posits that individuals act with free will should be held responsible for their behavior. Mentally ill individuals can be excused from moral, and sometimes legal, blameworthiness when they act in ignorance, under compulsion, or irrationally.

Many people in the lay community mistakenly believe that a crime is defined by the perpetrator's behavior so that a homicide is a homicide. In contrast, most criminal offenses require the presence of a physical element and a mental element. The physical element, the actus rea, refers to the actual behavior of the perpetrator, such as aiming and firing a weapon at the victim. The mental element, the mens rea, or guilty mind, addresses the state of mind of the perpetrator at the time of the offense. There are, for instance, several types and degrees of criminal homicide, and they usually are distinguished by the intent of the perpetrator, such as the presence of malice, criminal intent, or advance deliberation. In many states murder is charged in several degrees. Criminal homicides may be charged as involuntary manslaughter, voluntary manslaughter, third-degree murder, second-degree murder, or first-degree murder. The most serious homicide charge requires the presence of premeditation and deliberation by the defendant at the time of the crime. Each homicide crime has different mental elements, although all involve the killing of a victim by a defendant, and the punishments vary considerably among them.

The special defense of insanity builds on this inclusion of a mental element in the offense but advances it further to inquire about the defendant's state of mind beyond criminal intent. A defendant who makes detailed advanced preparations and then kills a person upon hearing voices from God commanding that act has criminal intent but may lack criminal responsibility for that offense, depending on the legal definition of insanity in the jurisdiction.

A handful of state jurisdictions in the United States have eliminated the legal defense of insanity. In those jurisdictions evidence regarding the defendant's mental illness at the time of the offense sometimes still can be introduced at trial to attempt to prove that the defendant did not have the requisite mental element or intent to commit the offense. Thus, if the defendant was so mentally ill that he or she could not have intended to commit the offense, then evidence of that illness and mental state is admissible at trial.

Legal Standards of Criminal Responsibility

Elements of the insanity defense are defined in different ways. The definition of the underlying mental disorder and the specific components of the defense are defined by state and federal statute but sometimes are defined by case (judge-made) law. The states vary widely in the definition, implementation, and outcome of the insanity defense.

Statutes and case law also describe the applicable procedural issues related to evaluations of criminal responsibility, such as the right of the defense and the prosecution to request an examination, the court appointment and payment of forensic experts to conduct the examination, and the extent of the waiver, if any, of the attorney client-privilege in conjunction with the examination.

For centuries courts, legislators, and policy makers have struggled to articulate an appropriate threshold and definition of legal insanity to exculpate a criminal defendant. The concept of a "wild beast" test was introduced centuries ago, excusing only individuals who did not know what they were doing because they resembled infants or wild beasts in their intellectual function. A New Hampshire court decision in 1868 (State v. Pike, 49 N.H. 399) offered the "product test" of insanity, stating, "No man shall be held accountable, criminally, for an act which was the offspring and product of mental disease." The product test subsequently was adopted in 1954 for the federal courts in the Washington, D.C., Federal Circuit. The product test was abandoned because of its breadth and concerns about abuse in light of the fact that symptoms of many mental disorders not deemed exculpatory can be expressed as criminal acts.

The contemporary legal standards for the insanity defense are composed of two principal factors: cognitive standards and volitional standards. Cognitive standards relate to the defendant's cognitive ability or actual knowledge of the criminality, illegality, or wrongfulness of his or her conduct at the time of the crime. Cognitive abilities include the ability to perceive reality accurately and make rational decisions that are based on that reality. Originating in the United Kingdom in 1843, the M'Naghten standard, for example, asks whether the defendant was suffering from 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." Wrong is defined variously as legally wrong (the defendant knew his or her action to be illegal) or morally wrong (the defendant knew his or her action to be morally wrong in his or her own eyes or in those of the public). As a symptom of severe mental illness, a command hallucination from God instructing a defendant to kill someone could be accompanied by an impairment in the defendant's cognitive ability or knowledge regarding wrongfulness. Cognitive tests of legal insanity are the most common test in the United States and characterize the legal insanity test used by the federal courts since 1984.

The alternative insanity defense standard is concerned with the defendant's ability to control his or her behavior at the time of the offense as a result of a mental disease or disorder. This volitional test asks whether the defendant lacked partial or total capacity to control the behavior that led to the offense independent of cognitive knowledge or appreciation of the offense and its wrongfulness. This standard originally was described as an "irresistible impulse test" in which the individual's desires were so strong that he or she could not help acting on them. The individual was in effect compelled to perform the criminal acts. Mental disorders such as bipolar disorder, with a euphoric mood, elevated energy, insomnia, impulsive behavior, and racing thoughts, can reduce an individual's ability to control his or her behavior.

There are several specific variations of the cognitive and volitional tests of insanity. A cognitive test that employs the language of the defendant's ability to appreciate the wrongfulness of his or her conduct is significantly different from one that relates to the defendant's ability to know its wrongfulness. Appreciation is a broader mental ability than simple knowledge and encompasses emotional as well as cognitive or intellectual abilities. Similarly, the test that asks whether a defendant lacks substantial capacity to conform her or his conduct to the requirements of the law is a looser or broader test than one that asks whether the defendant was unable to control herself or himself because of the mental illness.

The federal test of criminal responsibility, which was enacted by Congress in 1984 after the acquittal of John Hinckley, Jr., by reason of insanity for the attempted assassination of President Ronald Reagan, applies to federal crimes. It states: "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 severe mental disease or defect, was unable to appreciate the nature and quality or wrongfulness of his acts" (18 u.s.c. section 17a).

Some states use both a cognitive prong and a volitional prong. The American Law Institute (ALI) proposed a model test in 1962 through the Model Penal Code. The ALI test states: "A person is not responsible for criminal conduct if at the time of such conduct as a result of 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 law." This test had been adopted by approximately half the states before the Hinckley trial and the subsequent reforms.

Post-Hinckley Reforms of the Insanity Defense

After John Hinckley, Jr.'s, acquittal by reason of insanity in federal court many states as well as the federal government enacted changes to the insanity defense. Those changes included altering the test by making it stricter and changing certain procedures for its use. Some states and the federal courts eliminated the volitional test. Some states and the federal courts shifted the burden of proof at trial from the prosecution having the burden of proving that the defendant was not legally insane (beyond a reasonable doubt) to the defense, which must prove that the defendant was legally insane (by clear and convincing evidence). Other states added a guilty but mentally ill verdict to their criminal laws, offering a jury an alternative verdict to the insanity acquittal for mentally ill defendants who failed to satisfy the insanity defense requirements at trial.

Other statutory changes implemented stricter controls and supervision over individuals acquitted by reason of insanity, such as initial automatic hospitalization at least for psychiatric evaluation, with tighter procedures to prevent the premature release of dangerous individuals. Connecticut and Oregon have established special security review boards that intensively monitor insanity acquittees even on an outpatient basis, similar to criminal probation. Acquittees can be rehospitalized involuntarily if they are deemed to be too mentally ill or dangerous to remain in the community.

Clinical Evaluation

Statutes and case law variously use and define the terms mental disease, mental disorder, mental illness, and mental defect as the condition underlying a defendant's loss of cognitive or volitional function. The evaluator must be familiar with the legal definition of the term mental disease and the precise language of the criminal responsibility test in the defendant's jurisdiction. Statutes may or may not clearly define a mental disease or defect and usually do not employ accepted psychiatric nomenclature. Severe mental disorders such as schizophrenia, schizoaffective disorder, bipolar disorder, and other mood disorders with psychotic features generally qualify as mental diseases or defects for purposes of the insanity defense. Impulse control disorders such as kleptomania, pyromania, paraphilia, and pathological gambling may or may not be grounds for an insanity defense under the law. Other conditions not formally recognized as mental disorders by the mental health community, such as battered woman syndrome, may not constitute a mental disease or defect for purposes of the insanity defense.

The criminal responsibility evaluation is a retrospective evaluation of a defendant's criminal competency and is readily distinguished from an evaluation for treatment purposes. Therefore, forensic evaluators must have adequate training, experience, and forensic knowledge to conduct such evaluations properly. Evaluators typically attempt to interview the defendant about his or her thinking, behavior, and emotional controls at the time of the offense. However, evaluators cannot rely exclusively on the defendant's account of the crime because of the possibility of feigned mental illness and also must review crime scene data such as police reports, autopsies, witness accounts, and other information that can lead more objectively to an understanding of the events. Psychiatric treatment records of the defendant also are made available to the evaluator. Collateral interviews with family members or friends of the defendant, current treatment personnel, coworkers, and victims and witnesses also can be conducted. Psychological or neurological testing can be helpful in establishing a psychiatric diagnosis but cannot provide direct evidence that the defendant satisfies the insanity test standard. Evaluators may not be able to interview a defendant until months or years after the crime. Thus, reconstructing the defendant's mental state at that earlier time is a challenging task.

Clinical Issues

After the forensic mental health evaluator has obtained the necessary data regarding the defendant's mental health history and the defendant's state of mind at the time of the offense, the evaluator must provide to the retaining attorney or court an opinion about the defendant's psychiatric diagnosis and address the insanity defense standard. There are no biological tests that can prove directly whether a defendant had a mental disorder at the time of the crime or met the insanity defense standard, and the evaluator uses clinical judgment to reach conclusions in this regard. A defendant's assertion of a severe mental disorder at the time of the crime is more credible when there is a previous history of that disorder and documented treatment for it.

The evaluator must attempt to exclude mental conditions that are not deemed to be exculpatory by the applicable law. Personality disorders and intoxication by alcohol and drugs at the time of an offense are typically not exculpatory, and so the effects of those disorders on a defendant must be considered but separated from those of disorders that are potentially exculpatory. In other words, the evaluator must establish the relationship between the mental disorder present at the time of the offense and the criminal behavior.

There are many challenges in determining whether a defendant meets the legal insanity standard. The evaluator focuses on the defendant's thoughts, feelings, and behavior at the time of the crime but also inquires about those issues before and after the crime. If the defendant is charged with multiple crimes, the evaluator performs the analysis for each of those crimes. The evaluator must analyze the defendant's thoughts, feelings, and behavior carefully to determine whether the specific cognitive or volitional criteria for the applicable insanity defense are satisfied. It is likely that a defendant will satisfy the criteria for one insanity defense test but not for another.

If a jurisdiction uses a volitional insanity defense test, the evaluator must determine whether the defendant lacked the ability to control his or her behavior as a result of a severe mental disorder or simply failed to control his or her behavior because of anger, revenge, greed, envy, sexual arousal, or another condition unrelated to a severe mental disorder. The fact that a defendant acted on an impulse or desire does not mean that that impulse was irresistible; most, if not all, impulses can be resisted in certain circumstances. Volitional assessments involve a determination of whether the defendant attempted to delay or resist the impulse, pursued alternatives to gratifying the impulse, and planned or prepared for the crime while avoiding apprehension.

The insanity defense has been a complex yet compelling subject for centuries, attracting extraordinary public attention, especially after well-publicized crimes. The defense has survived many attempts to abolish it, with only a few states having done that. Although there are moral and legal bases for excusing an individual's criminal activity, most societies have struggled to adopt exculpatory rules that are politically acceptable and fair to mentally disordered individuals. Increasing attention has been paid in the United States to adopting postacquittal treatment and monitoring procedures to maximize the treatment of insanity acquittees while providing for the public safety.

robert m. wettstein

SEE ALSO: Autonomy; Behaviorism; Competence; Conscience; Freedom and Free Will; Mental Illness; Mentally Disabled and Mentally Ill Persons; Responsibility


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