Clark v. Arizona, 548 U.S. 735 (2006), is a United States Supreme Court case in which the Court upheld the constitutionality of the insanity defense used by Arizona.
The Court affirmed the murder conviction of a man with paranoid schizophrenia for killing a police officer.
The man had argued that his inability to understand the nature of his acts at the time that they were committed should be a sufficient basis for showing that he lacked the requisite mental state required as an element of the charged crime.
The Court upheld Arizona's restriction of admissible mental health evidence only to the issue of insanity and not to show that the defendant did not possess the required mental intent level necessary to satisfy an element of the crime. Evidence is admissible only to show that the defendant was insane at the time of the crime's commission.
In this case, the defendant knew right from wrong and so he could not qualify under Arizona's insanity defense.
Background
The constitutionality of an insanity defense was questioned as well as whether a defendant has a Fourteenth Amendment due process right, unrelated to the insanity plea, to present the correct evidence on the mental state to counter the prosecution's evidence of criminal intent.
In the case, Eric Clark shot and killed a police officer at a traffic stop because he believed his town in Arizona had been taken over by aliens. Clark, was diagnosed with paranoid schizophrenia and used the insanity defense to try to use his mental disorder as an excuse for the crime that he had committed.
The court did not believe that Clark's insanity defense was a justifiable defense, and he was sentenced to 25 years in prison. Throughout the court case, Clark presented an elaborate testimony describing his odd behavior a year prior to the incident. Among many other things, Clark believed that "aliens", some being government employees, were trying to hurt and kill him and that the only way to stop them was through death.
A psychiatrist testified that Clark has paranoid schizophrenia in which a patient has delusions that a person is against the patient and/or family. The psychiatrist said that at the time of the shooting, Clark was incapable of deciding right from wrong and so was insane.
Before being tried again, he was committed to a mental institution for two years, and his belief in aliens was still present afterward, but he believed that they were no longer out to get him but had another mission.
Decision
In a 5–4 decision, in favor of Arizona, the US Supreme Court decided that the Arizona court could limit the amount of evidence used to plea a person's sanity for a defendant's insanity defense. Justice Souter believed that having a defendant prove his insanity in order to justify they were unable to clearly think while committing the crime would disprove his claim for insanity because they were able to think clearly to prove they were insane. The court cited the Arizona Supreme Court's decision in State v. Mott, which refused to allow a psychiatric testimony to invalidate a criminal's intent and to uphold that Arizona does not allow evidence of a mental illness to neutralize the mens rea of a crime. Mens Rea is an element of criminal responsibility regarding whether or not there was intention or knowledge of wrongdoing while a crime was being committed. The court also determined that due process does not require a State to use both areas of the M'Naughten insanity test. Rather, a State may adopt an insanity test that focuses solely on moral incapacity.
Dissenting opinions
Judges Ginsburg, Kennedy, and Stevens disagreed with the majority ruling of the court. Justice Breyer partially concurred and agreed with the Court's "basic categorization" of evidence related to insanity. Further, he acknowledged that a State may provide consideration of mental-disease "solely in conjunction with the insanity defense." However, he dissented from the majority's opinion and would change the case so that Arizona courts could determine whether state law is consistent.
In dissent, Justice Kennedy stated that it was not necessary for him to address Clark's due process challenge to Arizona's insanity test. Instead, he disagreed with the majority for limiting Clark's claim to evidentiary support on his insanity. He also believed the Mott Rule, which does not allow evidence for insanity to prove someone is not guilty, to be unjust in the case as it is an exclusion of evidence, despite its credibility.