Supreme Court to Review Insanity Defense

The Supreme Court embarked on a potentially far-reaching review of the insanity defense yesterday, as the justices heard oral arguments in the case of an Arizona man, Eric Michael Clark, who was suffering from paranoid schizophrenia at the time he shot a police officer to death.

At issue in the case is whether Arizona's version of the insanity defense, which requires defendants to prove with "clear and convincing" evidence that they were too mentally ill to understand that their conduct was wrong, is so narrow that it violates the constitutional right to due process of law.

Clark's lawyer, David Goldberg, told the justices that the law denied Clark an opportunity to show at trial that, even if he was able to tell right from wrong, he could not have formed the requisite criminal intent -- in this case, the intent to kill a police officer.

Goldberg said that due process requires allowing a defendant to prove that, whatever his sense of right and wrong, he did not grasp "the nature and quality" of his acts. Goldberg noted that at the time of the killing, Clark was obsessed by the idea that aliens were stalking him and that he might have thought he was defending himself from an alien when he shot Flagstaff, Ariz., police officer Jeffrey Moritz.

Clark is supported in the case by the American Psychiatric Association and the American Psychological Association.

Arizona counters that its law gives defendants ample opportunity to introduce the relevant evidence of their mental illness. The state is backed by the Bush administration, which argues that, although the federal insanity defense law is more broadly worded than Arizona's, Congress's discretion might be limited by a ruling in favor of Arizona. A brief from 16 states also supports Arizona, arguing that a broad ruling in Clark's favor "will call into serious question the validity of the majority of state insanity statutes."

Although the insanity defense has deep roots in English common law, the Supreme Court has never ruled that the Constitution requires it. Many states revamped their insanity defense laws after a jury's finding that John W. Hinckley Jr. was not guilty by reason of insanity in the 1981 attempted assassination of President Ronald Reagan. Four states -- Idaho, Kansas, Montana and Utah -- have abolished the defense.

Arizona toughened its law in 1983 by raising the defendant's burden of proof, and again in 1994, when it replaced the "not guilty by reason of insanity" plea with "guilty except insane," the plea Clark entered.

If he had been found guilty except insane, Clark would have been committed to a mental hospital. Instead, he was found guilty of first-degree murder and sentenced to 25 years to life in prison.

The court's decision to hear Clark's case, which was summarily turned down by Arizona's Supreme Court, suggested that some justices saw insanity law as ripe for judicial review. But there were signs yesterday that they might be having second thoughts.

"I thought some of these questions might be in this case, but now I'm having doubts about that," Justice Stephen G. Breyer remarked.

Breyer noted that much of the evidence of severe mental illness that Clark would use to prove his delusions about aliens would also be introduced as part of proving whether he knew right from wrong.

Seeking to reinforce that point, Randall M. Howe of the Arizona attorney general's office told the court that "it would be difficult to imagine a situation where someone knew right from wrong, but not the nature of his act."

Justice Anthony M. Kennedy agreed with Howe. "I'm trying to think of some hypothetical where it would make a difference, and I can't come up with one."

But Justice John Paul Stevens challenged the state's position, asking Howe whether someone could be found guilty if he thought he was shooting a Martian and believed that killing Martians was acceptable.

Howe conceded that he might have a strong case of insanity but quickly added that "a state has a right to define insanity as it sees fit."

The case is Clark v. Arizona , No. 05-5966. A decision is expected by July.