Delling is currently serving a life term at a maximum security prison even though his trial judge found that he did not have the “ability to appreciate the wrongfulness of his conduct.” Delling’s lawyers argue that the insanity defense was the only one available to him.
“For centuries, the moral integrity of the criminal law has depended, in part, on the insanity defense,” Stanford law professor Jeffrey L. Fisher wrote in a petition on Delling’s behalf.
Punishment is traditionally justified on the basis of an individual consciously choosing evil over good, Fisher wrote. “Laws such as Idaho’s abandon that basic tenet,” he said.
Fisher contends that Idaho’s law violates the Constitution’s guarantee of due process of law, as well as the Eighth Amendment’s prohibition of cruel and unusual punishment.
According to one study, the insanity defense is rarely invoked and is successful only about 25 percent of the time. The Constitutional Accountability Center and the American Psychiatric Association support Delling’s case, along with a group of 52 law professors who told the Supreme Court that the affirmative defense of insanity is a matter of fundamental fairness.
The state of Idaho resisted Delling’s arguments when his case came before the state supreme court, but has not responded to his petition to the U.S. Supreme Court. The Court will decide whether or not to review Delling’s case later this year.