Constitution Daily

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Kahler v. Kansas: Can States Abolish the Insanity Defense?

October 8, 2019 by Robert Black


On Monday, the first day of the new Supreme Court term, the Court heard argument in Kahler v. Kansas, a case that could generate an entirely new line of constitutional jurisprudence. The case revolves around the “insanity defense,” an ancient doctrine under which people who committed crimes because of their severe mental illness would not be held legally culpable.

There have been any number of precise formulations of the standard for an insanity defense, but the common thread, until recently, is that insanity operated as an “affirmative defense.” An affirmative defense negates a defendant’s criminal liability, even if it is proven that the defendant committed the alleged acts. So even if the prosecution proves that the defendant had the requisite criminal intent, or “mens rea,” as well as having committed the act or crime itself—the “actus reus”—the defendant could still escape conviction by demonstrating insanity.

This is still true in almost every state today, but Kansas is one of several that has abolished insanity as a separate defense. Instead, a mentally ill defendant may try to argue that, because of their mental illness, they lacked general criminal intent, and therefore that the prosecution has failed to prove its case—but that’s it. James Kahler was convicted of murder and sentenced to death after he shot and killed his ex-wife, her mother, and two of their three children. Kahler raised his mental illness—chiefly depression, but also several personality disorders—at trial. But under Kansas law he could only argue that his conditions left him incapable of forming criminal intent, meaning in this context that he knew he was killing another person. His lawyers challenged that law as unconstitutional, and after the Kansas courts rejected his arguments the Supreme Court took the case to consider whether abolishing the insanity defense violates the 14th Amendment’s Due Process Clause or the Eighth Amendment’s Cruel and Unusual Punishment Clause.

What makes this case so fascinating is that the Court has never before held, or even been asked to consider, whether the states may abolish traditional pillars of criminal law like the insanity defense. Broadly speaking, this is something the states simply haven’t done. There is therefore no established framework for evaluating Kahler’s claim, and oral argument showed a Court deeply uncertain how to approach the matter. Unsurprisingly, arguments from history took center stage, with Kahler’s lawyer arguing that the insanity defense is deeply rooted in our nation’s history and tradition. (In fact, they contend, it traces back even further in English common law, to the 1500s at least.) The irreducible constitutional minimum, she suggested, requires states to recognize that those who are incapable of moral judgment and cannot tell the difference between right and wrong—a standard drawn from the 1843 British case R. v. M’Naghten—cannot be held criminally responsible for their actions.

Kansas, with the support of the U.S. Department of Justice, begged to differ. Even if the law has recognized insanity defenses in one form or another since time immemorial, they contended, no single formulation of the defense has ever been so uniformly adopted to be “deeply rooted” in our history. Furthermore, recognizing insanity as a separate defense, rather than an implicit result of general mens rea standards requiring criminal intent, is a relatively modern development. Kahler’s counsel responded that the ancient understanding of criminal intent was different from, and broader than, our mens rea rules, and it included the very notion of moral judgment that today is only considered through an affirmative insanity defense. The case therefore may require the Court to parse not only our Constitution, but centuries-old common law rules as well.

However, history was not the Court’s only concern. Justice Elena Kagan tried to probe the limits of Kansas’s argument, asking if a state could abolish other venerable defenses such as duress. Could states go so far as to make murder, or other crimes, into strict-liability offenses, where the defendant’s mental state would be irrelevant once it was proven that they committed the act of homicide? The state’s counsel largely avoided the question, saying that it would turn on the historical record and that they had not done the research to provide a definitive answer.

Conversely, the Justices pressed Kahler’s lawyer to specify exactly what standard she believed the Constitution required, and to confront earlier statements by the Court that it would not get into the business of formulating a standard as a matter of constitutional law. She responded that, while the Court should not choose one of the competing formulations to impose uniformly on the states, it should recognize a bedrock constitutional minimum above which the states are free to experiment.

Justice Stephen G. Breyer wanted to focus on the policy rationale behind Kansas’s system. He provided a hypothetical of two individuals, both insane, who each killed a man, one of whom believed they were killing a dog and one of whom believed they had been ordered to kill by a dog. The traditional insanity defense would excuse both killings, while Kansas’s law would excuse the former but not the latter, and Breyer wanted to hear why it made sense to treat these two defendants differently. Once again, clear responses were not forthcoming. Instead, both Kansas and the federal government argued that these are difficult questions whose answers are the states’ responsibility, not the Court’s.

Finally, Kahler’s lawyer sounded an interesting note in her rebuttal, saying that Kansas had gone against “what we believe as a country.” Consciously or otherwise, she was echoing Chief Justice Earl Warren, who would famously lean forward from the bench and ask, “But is it fair?” Professor Philip Bobbitt has cited Chief Justice Warren as a leading practitioner of argument from constitutional ethos, the bedrock American values—like fundamental fairness—embodied in our Constitution. The Court rarely relies on such arguments, but with text, history, and precedent offering such little guidance, perhaps Kahler is a chance for these considerations of basic values to shine.

It is difficult to predict how the Court will come out in this case, largely because the issue it presents is so novel. The Justices did not seem to line up as clearly hostile to one side or the other; instead, they each seemed to be trying to get a purchase on the case, to figure out how they should even go about analyzing this sort of constitutional claim. Whichever way the Justices go, however, Kahler looks to be a true landmark decision for generations to come.

Robert Black is Senior Fellow for Constitutional Content at the National Constitution Center.


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