In the case of A.J. Arave, Warden v. Thomas E. Creech in 1992, the United States Supreme Court ruled on whether Idaho's capital sentencing statute was unconstitutionally vague because it did not provide clear and objective standards for determining when a murder is "especially heinous, atrocious or cruel." The court held that while these terms are indeed broad and could be interpreted differently by different people, they were not unconstitutionally vague as long as there were other factors to consider in deciding if a crime met this standard. In this case, the jury had been instructed to also consider whether the defendant exhibited utter disregard for human life during his crime - an instruction which provided sufficient guidance according to Justice Sandra Day O'Connor who delivered the opinion of a unanimous court.

In the dissenting opinion for A. J. Arave, Warden v. Thomas E. Creech, Justice Blackmun argued that Idaho's capital sentencing statute was unconstitutionally vague and arbitrary because it failed to provide clear guidelines on how mitigating and aggravating factors should be weighed in determining a death sentence. He believed this lack of clarity could lead to inconsistent application of the death penalty across different cases, violating the Eighth Amendment's prohibition against cruel and unusual punishment by creating an unacceptable risk of arbitrariness in its imposition. Furthermore, he disagreed with the majority’s view that previous decisions provided sufficient guidance for juries making these determinations; instead asserting that such precedents were too general or case-specific to offer meaningful direction.