Kahler v. Kansas

Justice Breyer (34:34): Imagine two defendants. Both defendants, 1 and 2, are certified by whatever board of psychiatrists you want as totally insane. All right? The first defendant shoots and kills Smith. The second defendant shoots and kills Jones. The first defendant thinks that Smith is a dog. The second defendant knows it's a person but thinks the dog told him to do it. Okay? What's the difference?

Jareb Gleckel: Justice Breyer, I would answer this question in two parts. First, we want to figure out which defendants deserve to be punished. With respect to penological justifications, this falls under retribution. I like dogs at least as much as I like humans, so I’m going to change the hypothetical just slightly: a defendant hallucinates that a mannequin has come to life and has told him to shoot someone, versus the defendant who shoots a person thinking that person is a mannequin. If, in each instance, we step into the defendant’s world, we realize that only one defendant deserves retribution. We generally determine desert based on the facts as the defendant perceives them. It is never OK to shoot a person, even if a mannequin comes to life and insists on it. Yet if the second defendant believed he was shooting an inanimate object, then he does not deserve retribution.

As for the second part, I would observe that every insanity test requires line-drawing, and the “right vs. wrong” test requires line drawing that is even more arbitrary. If due process requires a defense for a person who, as a result of a biological disease/defect cannot tell right from wrong, why would it not also require an involuntary intoxication defense? A person who is involuntarily given certain drugs (e.g. LSD) will have a biological imbalance, through no fault of her own, that can impair her ability to understand right from wrong. And this may extend even farther to someone without a biological impairment. Arguably, someone who does not understand right from wrong because he was raised in a cult and brainwashed is no more culpable than someone who does not understand right from wrong due to a biological disease.

Samuel Alito (8:51): Well, what is the answer to my question? Is it sufficient if the person has something that is considered to be a mental disorder in the DSM? And it has been calculated that one in five people in the United States has some mental disorder. So we're talking about 60 plus -- 60 million plus people. All of them could go to the jury on the question of whether they had the capacity to know that what they were doing when they committed the crime was morally wrong.

John Blume: No, Justice Alito, a DSM diagnosis alone would not allow a defendant to go to the jury on insanity. There would be at least two other necessary conditions. First, one of the symptoms of the diagnosis would have to be a significant disturbance of thought. That is not true of many DSM disorders, including the most prevalent ones such as anxiety and personality disorders. Second, there would have to be a clear nexus between the mental disorder and the criminal offense. And third, as a practical matter, the defense would have to be able to secure the services of a mental health expert willing to testify under oath that -- as a result of the disorder -- the person met the legal standard for insanity, which no reputable mental health professional would do merely on the basis of a DSM diagnosis.