Does the Insanity Defense Have a Legitimate Role?

Apr 01, 2002

While the public perceives that many criminals escape punishment by pleading insanity, the truth is that very few people are ever found not guilty by reason of insanity. Society has to decide whether they want to lock up everyone who does any bad thing or excuse the behavior of people who are not capable of controlling their own behavior.

Public perceptions are that the insanity defense occurs far more commonly than records indicate. In fact, the insanity defense is used in less than 1% of criminal proceedings and is successful in approximately one-quarter of those cases. Furthermore, defendants who are found insane spend as much, or more, time in state custody than their criminally convicted counterparts. The media may foster the notion that criminals get away with feigning mental defect, only to be released and recidivate. However, the insanity plea is actually based on a long-standing legal tradition and is rarely successfully completed. In fact, approximately 70% of insanity acquittals result from agreements between opposing attorneys, in which the prosecution agrees that society would be better served by placing the defendant in treatment, rather than in prison (Blum, 1992; Bogenberger et al., 1987; Cirincione, 1996; Rogers et al., 1984; Smith and Hall, 1982).

Outside of assisting in sentencing, there are two places for mental disease in the legal system. The first is a defendant's ability to understand the trial process. People who do not understand the nature of the charges or the functioning of the legal system are considered unfit for trial. More germane to this article, if mental illness had a direct effect on a given criminal act, an individual can be found legally insane.

Harvard Law School professor Sheldon Glueck stated in 1927, "Perhaps in no other field of American law is there so much disagreement as to fundamentals and so many contradictory decisions in the same jurisdictions." The concept of insanity has changed over time and locale, but the basic notion of this defense is that some individuals, by reason of mental condition, are not capable of controlling or understanding their own unlawful behavior. However, the presence of a mental illness or other condition does not automatically predict a successful insanity finding.

A great historical pendulum swings between protective and punitive laws. In the normal course of events, laws slowly evolve to allow more and more efforts to treat those mentally ill offenders who can be safely removed from the prison population. Eventually, a psychotic individual commits a highly publicized crime, usually an assassination, and the lawmakers throw up their hands over "doctors dictating the law" and "getting criminals off the hook."

This happened in England in 1841, when the Prime Minister's secretary was killed by a delusional wood-turner from Scotland named Daniel M'Naughten. In this landmark mental health case, the defendant was found not guilty by reason of insanity (NGRI), and the Queen demanded an appellate ruling, resulting in the very strict "M'Naughten Rules" in 1843. These essentially said a person could be found insane if, at the specific time of a crime, they were unable to know the difference between right and wrong. This is known as a "knowledge-only" based test, with no room for uncontrollable impulses.

In the United States, this definition was considered by the courts but was seen as too restrictive. Instead, the American judiciary took a slightly different tack. For example, in Parsons v Alabama (1886), the State Supreme Court opined that a person was NGRI if they had lost "free agency" as a result of mental disease. This would allow an insanity defense if a person knew an act was illegal, but could not control their behavior.

Later, the American Law Institute (ALI) promulgated a Model Penal Code that included a two-pronged provision for insanity. Specifically, an individual 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 [wrongfulness] of his conduct or to conform his conduct to the requirements of the law." It is important to note the or, allowing either knowledge or impulse to be a basis for insanity. By the 1970s, most states had adopted these rules.

In 1981, President Ronald Reagan was shot by John Hinckley. Hinckley had incorporated scenes from a popular movie ( Taxi Driver) into his delusional system and was attempting to gain the love of a famous actress (Jodie Foster). He was found NGRI under the impulse control part of the ALI law, which led to hospitalization rather than imprisonment. Immediately, the federal government, and many states, tightened the insanity laws back to those of 1843 England.

Current Legal Requirements

Currently, the requirements for insanity vary by state. The typical standards require that a person be unable to differentiate between right and wrong at the time of the crime. The inability to appreciate the wrongfulness of conduct must be the direct result of a mental disease or defect. Such defects typically include psychotic disorders, mood disorders and organic conditions such as mental retardation. Virtually no state allows sociopathy to be grounds for an NGRI defense, and voluntary intoxication cannot by itself end culpability. Only a few states still contain the volitional question.

At the federal level, the Supreme Court, in USC Title 18, Chap 1, Sec 17, stated:

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 a severe mental disease or defect, was unable to appreciate the nature and quality or the wrongfulness of his acts. Mental disease or defect does not otherwise constitute a defense.

Some states have another legal option aside from insanity: guilty but mentally ill (GBMI). On its face, this seems to be a good idea, as jurors have several options. However, there are two inherent problems. First, juries have two choices that find a person guilty, but only one that finds them innocent, leading away from giving the benefit of doubt to the defendant. Additionally, the GBMI finding assumes that prisons will engage in the same level of treatment as a hospital, so that a defendant can be equally well-served in either setting. A GBMI finding also yields a set sentence, which the person will serve even if completely psychiatrically stabilized. Alternatively, the defendant may have to be released even if they are still ill.

Loopholes and Pitfalls

The existence of an insanity defense has always been controversial. There have been several attempts to "eliminate the loophole" and thereby force mentally ill individuals into prison. Several state decisions have noted that criminal intent is an absolutely necessary part of any crime. In recent years, some states have redefined their laws to focus more tightly on the mens rea, or guilty mind. Under those laws, a person must, as a result of a mental illness, lack the ability to willingly or knowingly commit an act. This looks at criminal intent, rather than psychiatric diagnoses, therefore claiming an end to criminals getting off free.

Of course, as previously noted, the truth is that there is no evidence to suggest that this defense has ever been widely misused. A minority of states (Montana, Idaho, Utah, Kansas and Nevada) have omitted the insanity defense per se entirely, instead allowing mental state to be raised only as a mitigating factor.

Some people favor the abolition of the insanity defense for reasons unrelated to political gain. They argue that far too often (certainly in our experience) a person who is chronically mentally ill is automatically found NGRI, even when the evidence would not convict them of a crime (Halpern, 1992). In addition, some critics see it as a simple plea bargain that saves time for the lawyers and judges and locks up a possibly innocent person for many years.

We would argue that in the absence of laws to force hospitalization of mentally ill offenders, many would go to prison and be victimized. This goes against all historical and humane thinking that some people truly cannot be held to general standards of conduct because of mental conditions over which they have no control.

Burden of Proof

Defining the burden of proof presents another issue in the insanity defense. Who has to prove what and how do they prove it? Since the average citizen is presumed to be sane, if they claim insanity, who decides? Does the prosecution have to prove defendants are not insane, or do the people who ask the court to find them not guilty by reason of insanity have to justify themselves? Most states have gone with the latter, but it certainly has not always been that way. In the aftermath of the Hinckley case, many states shifted the burden of proof to the defendant.

There has also been discussion on the amount of proof required. Should insanity be proved only by 51% (e.g., a preponderance of evidence), or does it need a standard of "beyond a reasonable doubt"? Generally, laws give the benefit to the accused and logically would not require more than the preponderance standard. This issue was addressed when, in State v Coffman (1864), California was the first jurisdiction to review M'Naughten officially. Soon after, in 1879, the Alabama Supreme Court, in Boswell v State, rendered an opinion that we see as holding to the spirit of the original insanity laws and which, in our opinion, reads well:

Since an unsound mind cannot form a criminal intentinsanity, when proved, is a complete defense, but no defense is more easily simulated, and the evidencemust therefore be carefully and considerably scannedThe workings of a diseased mind are so variant that it is difficult to lay down an absolute rule for the government of all cases. Each case must depend, more or less, on its own particular factsIt ought to be proved thatat the time he committed the act, he did not consider it a crime against the laws of God and natureIf there is any reasonable doubt as to sanity, the jury should acquit him.

Concluding Thoughts

Currently, insanity is a well-established defense in this country. Although efforts to eliminate this way of escaping punishment will continue to generate attention, it is unlikely that our laws will eliminate the essential difference between those who choose to break the law and those who cannot choose.


References 1. Blum A (1992), Debunking myths of the insanity plea. National Law Journal, April 20.
2. Bogenberger RP, Pasewark RA, Gudeman H, Beiber SL (1987), Follow-up of insanity acquittees in Hawaii. Int J Law Psychiatry 10(3):283-295.
3. Cirincione C (1996), Revisiting the insanity defense: contested or consensus? Bull Am Acad Psychiatry Law 24(2):165-176.
4. Halpern AL (1992), The insanity verdict, the psychopath, and post-acquittal confinement. Psychiatr Q 63(3):209-243.
5. Rogers JL, Bloom JD, Manson SM (1984), Insanity defenses: contested or conceded? Am J Psychiatry 141(7):885-888.
6. Smith GA, Hall JA (1982), Evaluating Michigan's guilty but mentally ill verdict: an empirical study. Journal of Law Reform 16:77-114.