Since John Hinckley shot President Reagan, the country has hosted a lively debate on the place of the insanity defense and evidence of mental illness in the criminal courtroom. On Wednesday, the Court will hear arguments in No. 05-5966, Clark v. Arizona, a case that squarely revives these considerations. The case poses two questions: (1) whether a state criminal law that permits the fact-finder to ignore evidence of mental illness when deciding if a defendant acted with the requisite mens rea of a crime violates due process; and (2) whether a state’s standard for a defense of mental insanity violates due process if it does not follow the M’Naghten Rule, which permits a defense of insanity both when the defendant was suffering from a mental illness that made him unable to appreciate the “nature and quality” of his acts and when he did not know that what he was doing was wrong.

David Goldberg of Flagstaff, Arizona, will argue on behalf of the petitioner, Eric Michael Clark. Randall M. Howe will argue on behalf of the respondent, the State of Arizona, and Solicitor General Paul Clement will argue on behalf of the United States as an amicus curiae in support of the respondent. The parties’ briefs are available here. The brief for the United States may be found here.

In June 2000, seventeen-year-old Eric Clark shot and killed Flagstaff Police Officer Jeffrey Moritz. Just before the shooting, Clark drove a pick-up truck around a neighborhood block numerous times while blaring loud music. In response, a nearby resident called the police. Officer Moritz reported to the scene and stopped Clark’s vehicle. When Moritz approached the vehicle, Clark opened fire. After an exchange of gunshots, Moritz was mortally wounded.

Clark was charged with first-degree murder under Arizona Revised Statute § 13-1105(A) for allegedly “intentionally or knowingly” causing the death of an officer. At trial, Clark put forth an affirmative defense of insanity under Arizona Revised Statute § 13-502(A), which provides in pertinent part: “A person may be found guilty except insane if at the time of the commission of the criminal act the person was afflicted with a mental disease or defect of such severity that the person did not know the criminal act was wrong.”

The trial court found that Clark did not meet his burden by clear and convincing evidence and found him guilty of first-degree murder.

Clark appealed his conviction, arguing, inter alia, that Section 13-502(A) violates the due process clause of the Fourteenth Amendment for two reasons. First, although the traditional M’Naghten Rule permits an insanity defense when the defendant was suffering from a mental illness that made him unable to appreciate the “nature and quality” of his acts or when he did not know that what he was doing was wrong, Clark contends that the Arizona law only encompasses the second prong. The appeals court found that there is no constitutional requirement to provide an insanity defense in the first place, and that individual states are free to enact these defenses as they see fit. Second, he argued that the statute does not allow for the possibility that a defendant’s evidence of mental defect or illness undermines the state’s mens rea evidence. However, the court found that Clark had not shown at trial that he was incapable of knowing that he was killing a police officer. And, regardless, under Arizona’s State v. Mott, a defendant is not permitted to present evidence of a “mental disorder short of insanity… to negate the mens rea element of a crime.”

After the Arizona Supreme Court denied Clark’s petition for discretionary review, the Supreme Court granted certiorari. Clark’s first claim at the Court repeats his earlier contention that Section 13-502(A) violates the Constitution by departing from the M’Naghten test, which – according to Clark, who details the history of the insanity defense – has deep roots in the common law. Moreover, he points out, twenty states and the federal government use the M’Naghten standard for insanity, while seventeen others and the District of Columbia use a version of the American Law Institute’s “even broader” insanity standard. Clark argues that the due process clause secures for eligible defendants the right to put forth a defense of insanity at least as broad as M’Naghten.

Addressing Clark’s M’Naghten claim, the state argues that it is not bound to incorporate an insanity defense in its criminal laws. The states have historically defined substantive criminal law, including whether and to what extent mental disease or illness will excuse criminal behavior, and the Court should be especially wary of infringing on this traditional province of states’ rights. It relies on Leland v. Oregon, in which the Court held that a state requirement that a defendant prove insanity beyond a reasonable doubt does not violate due process. Further, in Powell v. Texas, the Court stated that it should not be compelled to define an insanity test in constitutional terms. Contrary to Clark’s claim of historical support for M’Naghten, respondent contends that courts, in fact, have historically used many different iterations for the insanity defense. The state also disputes Clark’s reliance on the “nature and quality” language, suggesting that the focus of M’Naghten has always been on whether the defendant knew his actions were wrong. Finally, policy concerns show that the Court should defer to state legislatures’ determinations in this arena. If the Court were to constitutionalize a certain insanity standard, it would freeze current knowledge of mental disorder, inhibiting advances that could make today’s standards obsolete. Thus, Clark has failed to meet his “heavy burden” of proving that the “nature and quality” prong of M’Naghten is so fundamental to justice such that Arizona law does not comport with due process. However, even if the due process clause requires the “nature and quality” prong, Arizona’s statute necessarily includes , as understanding whether an act was wrong necessarily encompasses “an understanding of the act’s nature and quality.”

In Clark’s second claim, he again contends that Arizona law violates due process by forcing the fact-finder to ignore evidence of diminished mental state offered to combat evidence of mens rea. At trial, the prosecution contended that by blaring music loudly while circling the neighborhood, Clark was luring police to him in a plan to kill an officer. Clark counters that this behavior shows that he was suffering from a schizophrenic attack at the time. By forbidding him to offer such evidence, the Arizona standard made it impossible to present a complete defense and violated his right to procedural due process. Alternatively, if Mott were considered a “substantive redefinition of the mental-state element” of an offense rather than a procedural rule, its application still violates the due process clause. Though states are given wide leeway to define their criminal laws, it is a “fundamental principle” that a crime must be constituted from “an evil-meaning mind with an evil-doing heart.” When a state’s law seriously stretches that conception, it violates substantive due process. By refusing to consider evidence of mental illness when determining Clark’s mens rea, the trial court punished him more severely than it would have a sane person; in Clark’s case, the court assumed intent from inference, whereas for a normal person, the court would have needed to find beyond a reasonable doubt that the defendant did knowingly take an officer’s life.

The state first responds that the Court should respect the appeals court’s implied decision that, under state law, Clark waived this claim because he did not offer proof that his illness made him incapable of knowing he was killing an officer. If the Court does reach the merits, however, it should find that the states have historically had the power to define criminal laws. Under Mott, the Arizona Supreme Court confirmed that the legislature did not intend to allow evidence of mental disease or defect to negate mens rea. Respondent argues that the Court has considered this mens rea claim in three different cases, including Fisher v. United States. In Fisher, the trial court rejected the defendant’s request for a jury instruction that evidence of mental disease which does not rise to the level of insanity should be considered when contemplating mens rea. The Court declined to hold that the rejection violated due process, reasoning that the matter was of “local concern.” Thus, Arizona is within its constitutional bounds to create an “objective” standard of mens rea with regards to mental disease and defect, as states “may rationally determine that defendants who have mental illnesses that fall short of insanity are no less culpable than those who have no mental illness.”

Finally, Clark argues that even if the Constitution permits a state either to lower the insanity standard below the M’Naghten test or to abrogate an insane defendant’s mens rea defense, a state cannot do both, as the combined effect of these two standards is to make it impossible for a defendant suffering from a mental disease or defect to present “a complete defense”- a clear violation of due process.

The arguments of the United States largely mirror those of the state. Its interest in the case stems from the fact that although Congress has enacted the M’Naghten Rule to govern the federal insanity defense, the government wants Congress to maintain authority to alter the standard as it sees fit.