Kahler v. Kansas (U.S. Supreme Court, March 2020)
Due Process/Insanity Defense – Due process does not require that a state adopt an insanity test based on the defendant’s ability to recognize that his crime was morally wrong.
March 23, 2020.
The opinion discussed the differences between the “moral incapacity” insanity defense and the “cognitive capacity” insanity defense. Under the former, the test is whether the defendant’s mental illness left him unable to distinguish right from wrong, while the latter simply asks whether the defendant was aware of and understood his actions at the time he committed the crime.
At issue was whether Kansas’s exclusive use of the cognitive capacity test violated due process because it allowed the State to convict a defendant when the defendant could not distinguish his conduct as right or wrong. Kansas law simply states that a defendant may raise the insanity defense to show “that he lacked the culpable mental state required as an element of the offense charged.”
The Court held that due process does not require that a state adopt an insanity test based on the defendant’s ability to recognize that his crime was morally wrong. Looking through the legal history of the different forms of the insanity defense throughout the states, the Court concluded that “it is not for the courts to insist on any single criterion moving forward” and that the insanity defense “is a project for state governance, not constitutional law.”
Dissenting, Justice Breyer argued that Kansas had in effect eliminate “the core” of the insanity defense, which asks whether defendant, due to mental illness, lacked the mental capacity necessary for his conduct to be considered morally blameworthy.
On certiorari from the Supreme Court of Kansas
Opinion by Kagan, joined by Roberts, Thomas, Alito, Gorsuch, and Kavanaugh
Dissenting opinion by Breyer, joined by Ginsburg and Sotomayor
Click here to read the opinion.