Don't abolish the insanity defense

Don't abolish the insanity defense
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The insanity defense, a bedrock principle of American criminal justice, is suddenly in peril.

Aberrant laws in Kansas and four other states have decreed that a defendant can be guilty even if motivated by beliefs grossly out of touch with reality as a result of severe mental disorder. In other words, some defendants who are insane by any reasonable definition, who are unable to comprehend what they are doing, to understand whether it is right, or to control themselves, can still be convicted of murder and other serious crimes as long as they intended their actions.

The Supreme Court was asked to decide in Kahler v. Kansas if these laws are constitutional. To the astonishment of many defense attorneys, prosecutors, legal scholars and judges, the court recently answered yes. In doing so, it gave a green light to every state in the union to effectively abolish the insanity defense.

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We co-authored a “friend of the court” brief on behalf of 290 bipartisan law professors urging the court to declare the Kansas law unconstitutional. You won’t be surprised that we think the court’s decision poses a threat to one of the foundational principles of American criminal justice. The court was correct that states largely should be free to define crimes and defenses as they wish, but not by permitting such a deeply rooted legal principle to be erased from American law.

Under this much-misunderstood defense, a person can’t be punished for serious crimes if the criminal conduct was affected by severe mental disorder. Roughly speaking, the defendant does not deserve blame because he was incapable of being rational. Blame and punishment in such cases is unfair, unjust.

Some people, including some lawmakers, don’t like or understand this defense even though it’s been recognized in English law for 500 years and became part of the common law of every American state after the Revolution. But it exists for very good reasons.

Imagine a murder defendant who suffered from paranoid, delusional beliefs that the victim was somehow sucking the brain out of his head and must be killed to save the defendant’s life (a real case, by the way, with no hint of malingering). The killing would be intentional, but the defendant was not morally responsible and shouldn’t be legally responsible because his delusional beliefs rendered him unable to behave as a rational person.

For the same reason, we do not hold young children or people with severe dementia accountable for their conduct if they intentionally do something wrong. It is simply unfair to blame and punish such people, even though they may need to be trained or restrained, because they lack the capacity to understand the consequences of their actions.

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Fortunately, there is little evidence that the insanity defense is abused or results in any danger to society. In particular, defendants acquitted by reason of insanity typically are committed to secure forensic facilities until it is safe to release them.

It is no good answer to say, as Kansas does, that the defendant can be acquitted if mental disorder prevented the formation of the legally required intent. In rare cases, a defendant may be so detached from reality — by hallucinations, for example — that he does not know what he is doing and therefore lacks the intent to do it. But in virtually all cases, even severe mental disorder does not prevent defendants from forming the mental state required by the charged offense. 

Instead, the defendant’s disordered beliefs and sensory experiences provide the defendant with the reason to form the mental state, such as the delusional belief that he needs to act to save his life. Recall the defendant who thought his brain was being sucked out of his head. Almost all defendants motivated by serious disorder will be convicted under the Kansas scheme. Kansas’s alternative promotes injustice and is no substitute for an independent insanity defense.

The “originalist” Supreme Court failed to respect what must have been the expectation of our Founders. We hope and expect that state legislatures will decline to follow the court’s misguided invitation and will choose instead to preserve the moral integrity of American criminal law.

Stephen J. Morse is the Ferdinand Wakeman Hubbell Professor of Law, a professor of psychology and law in psychiatry, and associate director of the Center for Neuroscience & Society at the University of Pennsylvania.

Richard J. Bonnie is Harrison Foundation Professor of Medicine and Law and director of the Institute of Law, Psychiatry and Public Policy at the University of Virginia.