“The law has long recognized that criminal punishment is not appropriate for those who, by reason of insanity, cannot tell right from wrong,” wrote Justice Stephen Breyer in a three-page dissent joined by Justices Ruth Bader Ginsburg and Sonia Sotomayor. “If a defendant establishes an insanity defense, he is not criminally liable, though the government may confine him civilly for as long as he continues to pose a danger to himself or to others by reason of his mental illness,” Justice Breyer wrote.
In contrast, Idaho’s law mandates that a defendant’s “mental condition shall not be a defense to any charge of criminal conduct.”
Rather than a blanket insanity defense, Idaho’s approach permits defense lawyers to present evidence at trial that their client’s mental illness undercut his or her ability to form the necessary criminal intent.
Also, judges in Idaho are required at sentencing to consider the defendant’s capacity to appreciate the wrongfulness of the criminal conduct.
The issue arose in an appeal on behalf of John Joseph Delling, who pleaded guilty to two counts of second-degree murder and was sentenced to life in prison.
Mr. Delling, who has a history of mental illness, was under the delusion that former high school classmates and other associates were attempting to sap his “energy” and deplete his “power” in a way that would eventually kill him. Instead of allowing that to happen, Delling drew up a list of seven people he believed he needed to kill to save his own life.