The Supreme Court held Tuesday that state appellate courts may conduct a Clemons reweighing of aggravating and mitigating circumstances, and may do so in collateral proceedings as appropriate and provided under state law.

James McKinney received two death sentences in 1992 following his conviction of two counts of first-degree murder for the murders of Christine Mertens and Jim McClain. Under Supreme Court precedent, state judges may weigh “aggravating and mitigating circumstances” during sentencing for murder, and a defendant becomes eligible for the death penalty if at least one aggravating circumstance is found. After determining that the Mertens murder was conducted “in an especially heinous, cruel, or depraved manner,” the trial judge sentenced McKinney to death.

McKinney argued to the Court that the trial judge committed an error in not considering a mitigating circumstance, McKinney’s history of PTSD, during his sentencing, citing the Supreme Court decision in Eddings v. Oklahoma (1982), where the Court “held that a capital sentencer may not refuse as a matter of law to consider relevant mitigating evidence.” McKinney’s case was reviewed by the Arizona Supreme Court, which reweighed the aggravating and mitigating circumstances and upheld McKinney’s sentences.

McKinney argued that the Arizona Supreme Court erred in the reweighing of the circumstances, because he was entitled to a reweighing by a jury. He argued that his constitutional rights were violated under Clemons v. Mississippi (1990).

In the majority opinion, Justice Kavanaugh refuted McKinney’s argument that a jury was necessary in cases of collateral review of harmless errors, which is what Kavanaugh categorized this case as.

Justice Ginsburg dissented, joined by Breyer, Sotomayor, and Kagan. Ginsburg argued that this case is not a mere collateral review, rather it is a direct review of a “harmful” error. Ginsburg also noted the Supreme Court found Arizona’s capital sentencing regime unconstitutional in Ring v. Arizona (2002), and therefore would hold McKinney’s death sentences unconstitutional.