Facing a challenge from a man sentenced to death for killing four people, the US Supreme Court responded Monday by upholding one of the country's strictest laws on insanity pleas. James Kahler—who claimed he was suffering from depression when he killed his two daughters, their mother, and their great-grandmother in 2009—was blocked from pleading insanity at his Kansas trial, as a 1996 state law prevents a person from claiming they didn't know their acts were wrong due to mental illness. "A state rule about criminal liability ... violates due process only if it 'offends some principal of justice so rooted in the traditions and conscience of our people, as to be ranked as fundamental,'" Justice Elena Kagan wrote in a 6-3 decision, per Courthouse News. But "no insanity rule in this country's heritage or history was ever so settled." This ruling upheld the Kansas Supreme Court's finding that "due process does not mandate that a State adopt a particular insanity test."
Kagan noted "Kansas takes account of mental health at both trial and sentencing. It has just not adopted the particular insanity defense Kahler would like." A discussion "about how far, and in what ways, mental illness should excuse criminal conduct" is welcome "as new medical knowledge emerges and as legal and moral norms evolve." But "it is a project for state governance, not constitutional law." Justices Ruth Bader Ginsburg, Sonia Sotomayor, and Stephen Breyer dissented. Breyer wrote that Kansas "has eliminated the core of a defense that has existed for centuries," per the New York Times. In other decisions shared on the court's website—a change amid the COVID-19 pandemic—the court sided with North Carolina in a copyright fight, as well as favored Comcast in sending a racial discrimination lawsuit back to a lower court, per USA Today. (Arguments are now postponed.)