Ken M. Levy

Document Type



This Article falls into three general parts. The first part starts with an important question: is the insanity defense constitutionally required? The United States Supreme Court is currently considering this question in the case of Kahler v. Kansas. The Court actually refused to answer this question in 2012 when it denied certiorari to an appeal brought by John Joseph Delling, a severely mentally ill defendant who was sentenced to life in prison three years earlier for two murders. Delling never had the opportunity to plead the insanity defense because his home state, Idaho, had abolished it in 1982. By depriving Delling of the right to plead insanity, Idaho violated Delling's Fourteenth Amendment right to due process and his Eighth Amendment right against "cruel and unusual"punishment. Naturally, the same is true for many other mentally ill and disabled defendants who have been prosecuted in Idaho and in the other three states that have abolished the insanity defense: Kansas, Montana, and Utah. The second general part of this Article notes an insight that I stumbled upon in the course of researching the first part: the insanity defense and the mistake of law defense both require ignorance of the law, what I refer to as "normative ignorance." Indeed, normative ignorance is what makes both of these defenses exculpatory in the first place. Given this critical connection, there is a way for Idaho, Kansas, Montana, and Utah to resume compliance with the Constitution. Instead of reinstating the insanity defense per se, which might be politically unpopular, they should just broaden their mistake of law defense to include normative ignorance caused by cognitive incapacity that is itself caused by mental illness or disability. Still, this Article is not merely directed at these four western states. It is directed at the other forty-six states as well. Because they already have an insanity defense, they need not incorporate it into their mistake of law defense. But in the third general part, I will argue that they should still expand their mistake of law defense to cover defendants who either lack a reasonable opportunity to learn the law or reasonably but mistakenly infer from widely accepted norms or ethics that their conduct is lawful.