Criminal Law

Delling v. Idaho

At issue in Delling v. Idaho was whether the Fourteenth or Eighth Amendment mandates the availability of an insanity defense in criminal cases, an issue this Court reserved in Clark v. Arizona.

Case Summary

Throughout history—from ancient Greece to the British common law, from the American Founding to the rebirth of the nation in the wake of the Civil War—the integrity of the criminal justice system has necessitated the availability of an insanity defense. Because, as the Supreme Court has explained it, society justifies the imposition of criminal punishment when there is a breach of the “duty of the normal individual to choose between good and evil,” there is a deep-rooted principle of law that “[t]hose who are under a natural Disability of distinguishing between Good and Evil . . . are not punishable by criminal Prosecution whatsoever.”

Today, federal law and the law of forty-six states and the District of Columbia hold with tradition and maintain some form of an insanity defense in criminal cases. Four states, however, have abandoned their longstanding recognition of an insanity defense. Those four states, including Idaho, where Petitioner Delling was convicted and is currently imprisoned in solitary confinement, allow conviction of the insane in conflict not only with the vast majority of their sister states but also with a long history of moral and legal tradition. The trial court in Delling v. Idaho found that Delling suffered mental illness so strong that his delusions compelled him to murder his own friends, but he was unable to mount an insanity defense. Allowing such conviction and imprisonment is not only “unusual” in our history, but also “cruel,” in that it condemns a person incapable of distinguishing right from wrong.

As CAC argued in its brief, the Due Process Clause rejects criminal laws that “offend [a] principle of justice so rooted in the traditions and conscience of our people as to be ranked fundamental.” Similarly, “the Eighth Amendment’s ban on cruel and unusual punishment embraces, at a minimum, those modes or acts of punishment that had been considered cruel and unusual at the time the Bill of Rights was adopted.” The overwhelming historical and modern consensus that fundamental norms of justice prohibit criminal punishment of the legally insane demonstrates that a state’s failure to allow an insanity defense violates the Constitution’s guarantee of due process of law and prohibition against cruel and unusual punishment.

On July 16, 2012, Constitutional Accountability Center filed a brief in support of Supreme Court review of Delling’s petition for certiorari to ensure that states respect the rights of criminal defendants to due process of law and to be free of cruel and unusual punishments.

On November 26, 2012, the Supreme Court denied certiorari in the case, over a rare and powerful written dissent by three Justices from the denial of review, preserving the viability of this issue in the future.

Case Timeline

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