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Joseph Delling was mentally ill when he set out on a bike trip in 2007 that took him 6,500 miles and resulted in two murders and one attempted murder (with four other targets on the list). He says it was self-defense.
Delling believed that former classmates at Timberland High School in Boise, Idaho, were stealing his essence. In a preemptive strike, he hoped to end their lives before they could end his.
By all accounts, Delling was a violent person. He’d stalked people. He’d threatened people. He’d hit another student with an anti-theft device from a car, stating his intent to kill the other students for ruining his life. He’d been forced out of a university for his disturbing behavior.
When he was 21, he started out on his journey: he would terminate the threat to his life.
On March 20, Delling arrived in Tucson, Arizona, and shot Jacob Thompson, a student at the University of Arizona. Thompson survived to identify his assailant, but not before Delling had shot and killed David Boss at the University of Idaho and Bradley Morse in Boise. Boss and Thompson had known Delling in high school. Morse had attended a school nearby.
In court, Delling’s brother testified that Delling had believed his targets were “stealing his powers.” He’d become quite agitated over the idea and had caused some property damage that involved a request for police intervention. Then he’d gone to “take care of" the problem.
The trial court found that Delling suffered mental illness so intense that his delusions had compelled him to murder his former friends. He had not understood that it was wrong. However, in Idaho, he was unable to mount the type of insanity defense he would need. If he’d been able to form intent to kill a human being, then he was out of luck.
Idaho and three other states have modified the traditional understanding of the insanity defense. Indeed, Idaho provides that a “[m]ental condition shall not be a defense to any charge of criminal conduct.” Supposedly, this is not “intended to prevent the admission of expert evidence on the issue of any state of mind which is an element of the offense.” So, insanity is still relevant to criminal liability, but only in a restricted context.
According to several legal accounts of this case, Idaho permits the conviction of individuals who knew what they were doing, even if they did not have the capacity to fully understand the moral or legal status of the act.
Delling has schizophrenia. He intended to kill other people. He viewed his acts as necessary to save himself. Yet, his illness is relevant only if it had prevented him from forming deliberate intent to kill the others.
He was convicted of two counts of second-degree murder and given life in prison.
On appeal, Delling argued that the restricted insanity defense violated his right to due process. The Idaho Supreme Court concluded that his rights were protected, and affirmed his sentence.
The case went to the U.S. Supreme Court. This Court declined to hear the case in 2013, although three justices dissented. They stated concerns about the restriction. They recognized that Delling was mentally ill, but that Idaho’s restriction meant that his mental illness would have to prevent him from knowing that he was killing human beings. If he thought they were zombies or alien invaders in human form, then he might have a case.
The trial court did recognize that Delling did not appreciate the wrongfulness of his conduct. Had he been charged in a different state (as long as it wasn’t Kansas, Utah or Montana), the more traditional notions of mens rea might have gotten him an insanity acquittal.
Many legal and mental health experts believe that the issue is not yet settled and will be raised again in another case. People in the grip of a delusion can certainly form intent, without the intent being part of a lucid process.
One concern, however, is that other states might now see in the Supreme Court's hands-off decision a reason to become more restrictive in their own insanity defenses.
