Supreme Court says states can limit scope of insanity defense

The Supreme Court ruled the Constitution does not require Kansas to use a common form of the insanity defense, one that allows criminal defendants to avoid conviction if they can show their mental illness prevented them from recognizing their criminal act was morally wrong.

Kansas eliminated that version of the insanity defense about two decades ago. It instead allows defendants to argue they lacked the required intent to commit the crime with which they were charged. Defendants may also argue for more lenient sentences based on mental illness.

The case concerned James Kahler, who was sentenced to death in 2011 for killing four family members. His lawyers said he had severe depression that made it impossible for him to understand reality or distinguish right from wrong. Under the Kansas law, similar to those of Alaska, Idaho, Montana and Utah, Kahler was barred from raising the defense his mental illness prevented him from knowing his actions were wrong.