If a person pleads "not guilty by reason of insanity" (NGRI), that plea means that the person committed the underlying act (that would have been criminal had she had the requisite mens rea, or guilty mind), but, because of mental illness, is not to be held responsible for that act. A series of perplexing and difficult questions remains: What should the test be to determine if a defendant is not criminally responsible for her act? If a person is found NGRI, what procedures are to be followed subsequent to the insanity acquittal? And, what do we know about the use of the plea, its success rate, and its implications for those who plead it?
Notwithstanding centuries of jurisprudential evolution, the insanity defense doctrine remains incoherent. Most judges, legislators, scholars, mental health professionals, social policy makers, jurors, journalists, and the public at large would agree with this proposition. This consensus is consistent whether the observer is a retentionist, a modified retentionist, an expansionist, or an abolitionist. Moreover, fixation on questions fundamentally irrelevant to the core jurisprudential inquiry of whom we shall exculpate has resulted in doctrinal stagnation. Immobilized by this irresoluble debate, we continue to ignore even more fundamental questions, such as why we feel the way we do about the "insane" and why, in further structuring the insanity defense, we remain willfully blind to new scientific and empirical realities.
The development of the insanity defense has tracked the tension between psychodynamics and punishment, and reflects our most profound ambivalence about both. On the one hand, we are especially punitive toward persons with mental disabilities who have been charged with crime, characterized by Deborah Scott and her colleagues as "the most despised and feared group in society" (1982); on the other, we recognize that in some narrow and carefully circumscribed circumstances, exculpation is—and historically has been—proper and necessary. This ambivalence infects a host of criminal justice policy issues that involve mentally disabled criminal defendants beyond insanity defense decisionmaking: on issues of expert testimony, mental disability as a mitigating (or aggravating) factor at sentencing and in death penalty cases, and the creation of a "compromise" guilty but mentally ill (GBMI) verdict. And the dissonances, tensions, and ambivalences reflected in insanity defense policy continue to control the public's psyche.
This entry will proceed in this manner. First, it will review the development of substantive insanity defense doctrine, and procedures followed after an insanity acquittal. Next, it will consider the impact of the John Hinckley case on subsequent doctrinal developments. Then, it will examine the empirical myths that underlie much of the insanity defense debate. Finally, it will look briefly at the abolition movement.
Development of insanity defense doctrine
Pre- M'Naghten history. The development of the insanity defense prior to the mid-nineteenth century tracked both the prevailing scientific and popular concepts of mental illness, "craziness," responsibility, and blameworthiness. In existence since at least the twelfth century, the defense has always aroused more discussion than any other topic of substantive criminal law, despite that fact that there were few insanity pleas entered prior to the mid-eighteenth century. Prior to the 1843 M'Naghten decision, the substantive insanity defense went through three significant stages: the "good and evil" test, the "wild beast" test, and the "right and wrong" test.
"Good and evil." The "good and evil" test apparently first appeared in a 1313 case involving the capacity of a child under the age of seven. The test reflected the moral dogmata of the medieval theological literature. The insane, like children, were incapable of sinning against their will since, according to the research done by Bernard Diamond and a colleague, man's freedom "is restrained in children, in fools, and in the witless who do not have reason whereby they can choose the good from the evil (1233)."
"Wild beast." The "wild beast" test appeared in Rex v. Arnold, an 1812 case in which the defendant had shot and wounded a British Lord in a homicide attempt. Judge Tracy instructed the jury that it should acquit by reason of insanity in the case because "a mad man . . . must be 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, such a one is never the object of punishment."
The emphasis was on lack of intellectual ability, rather than the violently wild, ravenous beast image that the phrase calls to mind; the test continued to be used until at least 1840.
"Right and wrong." The "right and wrong" test (the true forerunner of M'Naghten ) emerged in two 1812 cases; in the second of the two, the jury was charged that it must decide whether the defendant "had sufficient understanding to distinguish good from evil, right from wrong . . ." (Bellingham's Case, pp. 477, 671). The test was expanded upon in 1840 in Regina v. Oxford where the jury was told that it must determine whether the defendant, "from the effect of a diseased mind," knew that the act was wrong, and that the question that must thus be answered was whether "he was quite unaware of the nature, character, and consequences of the act he was committing" (546–47).
Even with these rigid tests in place, the public's perceptions of abuse of the insanity defense differed little from its reactions in the aftermath of the Hinckley acquittal nearly a century and a half later. The public's representatives demanded an "all or nothing" sort of insanity, a conceptualization that has been "peculiarly foreign" to psychiatry since at least the middle of the nineteenth century.
M'Naghten. In 1843, the "most significant case in the history of the insanity defense in England" (Perlin, Jurisprudence, at 79) arose out of the shooting by Daniel M'Naghten of Edward Drummond, the secretary of the man he mistook for his intended victim: Prime Minister Robert Peel. After nine medical witnesses testified that M'Naghten was insane, and after the jury was informed that an insanity acquittal would lead to the defendant's commitment to a psychiatric hospital, M'Naghten was found not guilty by reason of insanity (NGRI).
In response to Queen Victoria's fury over the verdict, the House of Lords asked the Supreme Court of Judicature to answer five questions regarding the insanity law, and the judges' answers to two of these five became the M'Naghten test:
[T]he jurors ought to be told in all cases that every man is 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 defence on the ground of insanity, it must be clearly proved that, at the time of the committing of the act, the party accused was labouring 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 (722).
The M'Naghten Rules reflected a theory of responsibility that was outmoded far prior to its adoption, and which bore little resemblance to what was known about the human mind, even at the time of their promulgation. Nonetheless, with almost no exceptions, they were held as sacrosanct by American courts that eagerly embraced this formulation, and codified it as the standard test "with little modification" in virtually all jurisdictions until the middle of the twentieth century.
Irresistible impulse. There was some interest in the post-M'Naghten years in the so-called irresistible impulse exception that allowed for the acquittal of a defendant if his mental disorder moved him to be unable to resist committing an offense he fully understood to be wrong. However, this formulation was not more than a transitory detour in the development of an insanity jurisprudence. Where it has generally been applied, it has been used in conjunction with M'Naghten, rather than by itself.
Durham. The first important theoretical alternative to M'Naghten emerged in the District of Columbia in the 1954 case of Durham v. United States. Writing for the court, Judge David Bazelon rejected both the M'Naghten and the irresistible impulse tests on the theory that the mind of man was a functional unit, and that a far broader test would be appropriate. Durham thus held that an accused would not be criminally responsible if his "unlawful act was the product of mental disease or mental defect" (1874–75).
Durham was the first modern, major break from the M'Naghten approach; as a result, the District of Columbia became a laboratory for consideration of the details of insanity, in its fullest substantive and procedural ramifications. Within a few years, however, Durham was judicially criticized, modified, and ultimately dismantled by the D.C. Circuit. The test's burial was completed by the 1972 decision in United States v. Brawner to adopt the Model Penal Code/American Law Institute test.
United States v. Brawner. Brawner discarded Durham 's "product" test, but added a volitional question to M'Naghten 's cognitive inquiry. Under this test, a defendant would not be responsible for his criminal conduct if, as a result of mental disease or defect, he "lack[ed] substantial capacity either to appreciate the criminality of his conduct or to conform his conduct to the requirements of law" (979).
Although the test was rooted in M'Naghten, there were several significant differences. First, the test's use of the word "substantial" was meant to respond to case law developments that had required "a showing of total impairment for exculpation from criminal responsibility" (p. 87). Second, the substitution of the word "appreciate" for the word "know" showed that "a sane offender must be emotionally as well as intellectually aware of the significance of his conduct" (p. 87), and "mere intellectual awareness that conduct is wrongful when divorced from an appreciation or understanding of the moral or legal import of behavior, can have little significance" (p. 87). Third, by using broader language of mental impairment than had M'Naghten, the test captured both the cognitive and affective aspects of impaired mental understanding. Fourth, the test's substitution in the final proposed official draft of the word "wrongfulness" for "criminality" reflected the position that the insanity defense dealt with an impaired moral sense rather than an impaired sense of legal wrong.
It was assumed that the spreading adoption of Brawner would augur the death of M'Naghten, an assumption that—in the light of the attempted assassination of then-President Ronald Reagan and the subsequent passage of the Insanity Defense Reform Act (IDRA)—has proven to be totally inaccurate. Brawner, did, however, serve as the final burial for the Durham experiment.
Guilty but mentally ill (GBMI). Perhaps the most important post-Brawner development in substantive insanity defense formulations has been the adoption in over a dozen jurisdictions of the hybrid "guilty but mentally ill" (GBMI) verdict, adopted, ostensibly, in the words of a Michigan state case (People v. Seefeld ), to "protect the public from violence inflicted by persons with mental ailments who slipped through the cracks of the criminal justice system" (290 Mich. App. 123, 124 (ct. app. 1980)).
The rationale for the passage of GBMI legislation was that the implementation of such a verdict would decrease the number of persons acquitted by reason of insanity, and would assure treatment of those who were GBMI within a correctional setting. A GBMI defendant would purportedly be evaluated upon entry to the correctional system and be provided appropriate mental health services either on an in-patient basis as part of a definite prison term or, in specific cases, as a parolee or as an element of probation.
Practice under GBMI statutes reveals that the verdict does little or nothing to ensure effective treatment for mentally disabled offenders. As most statutes vest discretion in the director of the state correctional or mental health facility to provide a GBMI prisoner with such treatment as she "determines necessary" (p. 65), the GBMI prisoner is not ensured treatment beyond that available to other offenders. A comprehensive study of the operation of the GBMI verdict in Georgia revealed that only three of the 150 defendants who were found GBMI during the period in question were being treated in hospitals.
Post-insanity acquittal procedures. In 1983, the Supreme Court—in Jones v. United States —made it clear that different procedural rules could apply to individuals hospitalized pursuant to an insanity acquittal than to persons who had been involuntarily civilly committed. The Jones court—over a strong and impassioned dissent—concluded that, because a successful insanity defense established beyond a reasonable doubt that the defendant committed the underlying criminal act, it was reasonable to conclude that such a person remained dangerous, mentally ill, and in need of treatment. Thus, it was not unconstitutional to force an insanity acquittee to bear the burden of proof at a release hearing, nor was it unconstitutional for such a person to be institutionalized for a longer period of time than would have been permissible had she been given the maximum sentence for the underlying crime.
Some states provide more liberal procedures. For instance, in State v. Krol (a case that predates Jones by eight years), the New Jersey Supreme Court found that there was little difference between commitments initiated through a civil process and those begun through a criminal process, and provided substantially identical procedures for both universes.
Hinckley and its aftermath
The insanity acquittal of John W. Hinckley for the attempted murder of President Ronald Reagan in 1981 galvanized the American public in a way that led directly to the reversal of 150 years of study and understanding of the complexities of psychological behavior and the relationship between mental illness and certain violent acts. The public's outrage over a jurisprudential system that could allow a defendant who shot an American president on national television to plead "not guilty" (for any reason) became a river of fury after the jury's verdict was announced.
Sensational trials such as Hinckley's consume the hearts and minds of the American public. They reflect our basic dissatisfaction with the perceived incompatibility of the due process and crime control models of criminal law, and with the notion that psychiatric "excuses" can allow a "guilty" defendant to "beat a rap" and escape punishment. Such dissatisfaction leads to a predictable response, especially when the defendant—like Hinckley—is perceived as one not sufficiently "like us" so as to warrant empathy or sympathy. As Loren Roth has suggested, when a "wrong verdict" is entered in a sensational trial, the American public may simply be nothing more than a "bad loser" (Perlin, Borderline, at 1380).
Members of Congress responded quickly to the public's outrage by introducing twenty-six separate pieces of legislation designed to limit, modify, severely shrink, or abolish the insanity defense; the debate on these bills illuminates with clarity the character of the legislative decisionmaking process. Statements by legislators introducing these bills or by Reagan Administration spokespersons supporting them reflected the fears and superstitions that have traditionally animated the insanity debate, as well as the public's core ambivalence about mentally disabled criminal defendants.
The legislation ultimately enacted by Congress—legislation that closely comported with the public's moral feelings—returned the insanity defense to status quo ante 1843, the year of M'Naghten. Besides relocating the burden of proof in insanity trials to defendants (18 U.S.C. § 17), establishing strict procedures for the hospitalization and release of defendants found not guilty by reason of insanity (18 U.S.C. § 4243 et seq.), and severely limiting the scope of expert testimony in insanity cases (Federal Rules of Evidence 704 (b)), the IDRA discarded the ALI–Model Penal Code test, and adopted a more restrictive version of M'Naghten, by specifying that the level of mental disease or defect that must be shown to qualify be "severe" (18 U.S.C. § 17(a)).
Prior to the Hinckley trial, the burden of proof in all federal courts (and in about half the states) was on the prosecution to prove a defendant's sanity beyond a reasonable doubt. Many observers placed the "blame" for the jury's subsequent acquittal on this allocation, and the question of burden shifting became a major subject of controversy at the subsequent Congressional insanity defense hearings. The IDRA responded to these concerns and placed the burden of proof in insanity defense cases on the defendant, and specified a burden of proof of "clear and convincing evidence."
This change was significant for two main reasons. First, symbolically, it underscored Congress's dissatisfaction with a system that appeared to make it "easier" for jurors to acquit in insanity cases. Second, empirically, by making the quantum greater than a preponderance (previously, the standard allocation in jurisdictions where the burden was on the defendant to prove insanity), it gave researchers the opportunity to investigate the "real life" impact of both the burden shift (as to party) and the especially heavy quantum of proof that the defendant will be responsible to prove.
The states quickly followed the lead of the federal government. Two-thirds of all states reevaluated the defense; as a result, twelve states adopted the guilty but mentally ill (GBMI) test, seven narrowed the substantive test, sixteen shifted the burden of proof, and twenty-five tightened release provisions in the cases of those defendants found to be NGRI. Three states adopted legislation that purported to abolish the defense, but actually retained a mens rea exception.
Empirical data and myths
Researchers agree that, in the small universe of successful insanity defense pleaders, a person with a history of major mental illness, who has sought help for that illness, and whose victim is a member of the immediate family (certainly a non-stranger) will be most likely to be found NGRI by a jury. Both successful and unsuccessful insanity pleaders are more frequently single, caucasian, somewhat older, and better educated than the usual defendant group, unemployed at the time of the insane offense, and with a history characterized by chronic unemployment, prior psychiatric treatment, drug abuse, alcohol abuse, and previous arrests.
In the wake of the Hinckley verdict, commentators began to examine carefully the "myths" that had developed about the insanity defense, in an effort to determine the extent to which this issue has been distorted in the public eye. The research shows that (1) the insanity defense opens only a small window of nonculpability; (2) defendants who successfully use the NGRI plea "do not beat the rap"; and, perhaps more importantly, (3) the tenacity of these false beliefs in the face of contrary data is profound.
Myth #1: The insanity defense is overused. All empirical analyses have been consistent: the public at large and the legal profession (especially legislators) dramatically and grossly overestimate both the frequency and the success rate of the insanity plea, an error that is undoubtedly abetted by the media's bizarre depictions, distortions, and inaccuracies in portraying individuals with mental illness charged with crimes. The insanity defense is used in only about 1 percent of all felony cases, and is successful just about one-quarter of the time.
Myth #2: Use of the insanity defense is limited to murder cases. In one jurisdiction where the data have been closely studied, contrary to expectations, slightly less than one-third of the successful insanity pleas entered over an eight-year period were reached in cases involving a victim's death. Further, individuals who plead insanity in murder cases are no more successful in being found NGRI than persons charged with other crimes.
Myth #3: There is no risk to the defendant who pleads insanity. Defendants who asserted an insanity defense at trial, and who were ultimately found guilty of their charges, served significantly longer sentences than defendants tried on similar charges who did not assert the insanity defense. Unsuccessful NGRI pleaders are incarcerated for a 22 percent longer time than individuals who never raise the plea (Braff, Arvantes, Steadman, Detention Patterns of Successful and Unsuccessful Insanity Defendants, 21 Criminal. 439, 445 (1983)). The same ratio is found when only homicide cases are considered.
Myth #4: NGRI acquittees are quickly released from custody. Of the entire universe of individuals found NGRI over an eight-year period in one jurisdiction, only 15 percent had been released from all restraints; 35 percent remained in full custody, and 47 percent were under partial court restraint following conditional release. A comprehensive study of California practice showed that only 1 percent of insanity acquittees were released following their NGRI verdict and that another 4 percent were placed on conditional release; the remaining 95 percent were being hospitalized. In other recent research, Stephen Golding and his colleagues discovered, in their study of all persons found NGRI in the Canadian province of British Columbia over a nine-year period, that the average time spent in secure hospitalization or supervision was slightly over nine and one-half years.
Myth #5: NGRI non-murderer acquittees spend much less time in custody than do defendants convicted of the same offenses. Contrarily, two-thirds of the NGRI acquittees—those who are not murderers—spend almost double the amount of time that defendants convicted of similar charges spend in prison settings, and often face a lifetime of post-release judicial oversight. In California, while the length of confinement for individuals acquitted by reason of insanity on murder charges was less than for those convicted, defendants found NGRI for other violent crimes were confined twice as long as those found guilty of such charges, and those found NGRI of nonviolent crimes were confined for periods over nine times as long.
Myth #6: Criminal defendants who plead insanity are usually faking. This is perhaps the oldest of the insanity defense myths, and is one that has bedeviled American jurisprudence since the mid-nineteenth century. Of the 141 individuals found NGRI in one jurisdiction over an eight-year period, there was no dispute that 115 were persons with schizophrenia (including 38 of the 46 cases involving a victim's death), and in only three cases was the diagnostician unwilling or unable to specify the nature of the patient's mental illness. Also, most studies show that 80–84 percent (see Perlin, Jurisprudrence, at 111 n.178), depending on study, of NGRI defendants have significant histories of prior hospitalizations.
Myth #7: Most insanity defense trials feature "battles of the experts." The public's false perception of the circus-like "battle of the experts" is one of the most telling reasons for the rejection of psychodynamic principles by the legal system. A dramatic case such as the Hinckley trial thus "reinforced the public's perception that the insanity defense is characterized by battles of experts [who] overwhelm" the jury, engendering judicial and public skepticism as to the ability of psychiatrists to actually come to reasoned and reasonable judgments in cases involving mentally disabled individuals charged with crime.
The empirical reality is quite different. In a Hawaii survey, there was examiner congruence on insanity in 92 percent of all cases; in Oregon, prosecutors agreed to insanity verdicts in 80 percent of all cases. Most importantly, these are not recent developments: over thirty-five years ago, a study of the impact of the Durham decision in Washington, D.C., found that between twothirds and three-quarters of all insanity defense acquittals were uncontested. In short, the empirical evidence refuting this myth has been available to judges, legislators, and scholars since almost a decade prior to the adoption of the ALI–Model Penal Code test in Brawner.
Myth #8: Criminal defense attorneys—perhaps inappropriately—employ the insanity defense plea solely to "beat the rap." Attorneys representing mentally disabled defendants have—for decades—been routinely criticized for seeking refuge in the insanity defense as a means of technically avoiding a deserved conviction. In reality, the facts are quite different. First, the level of representation afforded to mentally disabled defendants is frequently substandard. Second, the few studies that have been done paint an entirely different picture; lawyers also enter an insanity plea to obtain immediate mental health treatment for their client, as a plea-bargaining device to insure that their client ultimately receives mandatory mental health care, and to avoid malpractice litigation. Third, the best available research suggests that jury biases exist relatively independent of lawyer functioning, and are generally not induced by attorneys.
Since the mid-1980s, researchers and other scholars have been patiently rebutting these myths. The publication by Henry Steadman and his colleagues of their extended multi-jurisdiction study of virtually every empirical facet of insanity defense pleading proves—beyond any doubt—that the basic tenets are mythic. The extent to which the dissemination of these data alters the terms of the insanity defense debate will reveal whether these myths, in fact, can be reinterpreted by lawmakers and the general public.
The abolitionist movement
While the movement to abolish the insanity defense dates to the turn of the century, its contemporaneous revival can be traced to the Nixon Administration's unsuccessful attempts to limit its use to cases where the defendant, by mental disease or defect, "lacked the state of mind required as an element of the offense charged" (S.1, 94th Cong., 1st sess., 6522 (1975). Perlin, unpacking at 670). This proposed limitation has been characterized as the "lemon squeezer" exception: the defense would apply only where the defendant thought the strangulation-victim's head was a lemon.
Henry Steadman and his colleagues have published important data giving us some inklings as to what actually happens when abolition is attempted. Their research reveals that, basically, "abolition" in Montana was a pretext. First, "abolition" had no meaningful statistical impact on the number of defendants pleading NGRI. Defendants continued to allege that they lacked the requisite mens rea for criminal responsibility.
Second, defendants who previously would have been found NGRI are now found incompetent to stand trial. Two-thirds of these were subsequently committed indefinitely to state hospitals where they were frequently treated on the same units as patients who had been found NGRI prior to abolition "reform." In short, the insanity statutes were reformed, but the detention system was not. It is certainly possible that some of the post-"abolition" pleas were the result of defense counsel wanting to "flag" for the court that the defendants were seriously mentally ill, and in need of psychiatric hospitalization. This is precisely the same strategy often employed by counsel in jurisdictions where the defense has not been abolished.
It is not yet clear what impact Steadman's empirical breakthrough will have on politically motivated abolitionist measures. If the Montana experience is a representative one, then the full measure of the abolition charade is clear. The defense is "abolished" in name, but the plea is entered for pretextual reasons. Severely mentally ill criminal defendants are treated in the same wards of the same forensic hospitals to which they would have been sent had they been found NGRI. This suggests the meretriciousness of much of the politically based abolition movement: voters are being told that their representatives are "doing something" about the crime problem, but only the labels describing the patients' forensic status change.
The insanity defense has always been part of the fabric of criminal law. It is used rarely, successfully more rarely, and its "successful" use generally brings with it significant costs to the pleader (in terms of both stigma and length of institutional stay). The defense remains a prisoner of both behavioral and empirical myth; although these myths bear virtually no resemblance to reality, they have come to symbolize the public's perception of the defense and the plea. It is doubtful that any other area of criminal law is more poorly understood.
Michael L. Perlin
See also Competency to Stand Trial; Diminished Capacity; Excuse: Theory; Mens Rea; Mentally Disordered Offenders; Psychopathy.
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Bellingham's Case, Old Bailey Session Papers 263 (1812) (no. 433).
Durham v. United States, 214 f. 2d 862 (D.C. Cir. 1954), overruled in United States v. Brawner, 471 f. 2d (D.C. Cir. 1972).
Jones v. United States, 463 U.S. 354 (1983).
M'Naghten's Case, 8 Eng. Rep. 718 (1843).
Regina v. Oxford, 9 Carr, & P. 525 (1840).
Rex v. Arnold, 16 How. St. Tr. 695 (1724).
State v. Krol, 344 A. 2d 289 (N.J. 1975).
United States v. Brawner, 471 F. 2d 969 (D.C. Cir. 1972).
PERLIN, MICHAEL L.. "Excuse: Insanity." Encyclopedia of Crime and Justice. 2002. Encyclopedia.com. (August 29, 2016). http://www.encyclopedia.com/doc/1G2-3403000114.html
PERLIN, MICHAEL L.. "Excuse: Insanity." Encyclopedia of Crime and Justice. 2002. Retrieved August 29, 2016 from Encyclopedia.com: http://www.encyclopedia.com/doc/1G2-3403000114.html