Eighteen years ago, the U.S. Supreme Court's landmark Ring v. Arizona opinion held that a judge cannot unilaterally call for the death penalty; the Sixth Amendment right to a jury trial requires that jurors first determine the ultimate punishment is warranted.

But because the justices later clarified that Ring did not retroactively apply to sentences already reviewed and affirmed by state appellate courts, an estimated 97 death row prisoners still await execution on judges' orders — without a jury of their peers ever having agreed that they should die for their crimes.

Last week, one of those inmates suffered a likely fatal setback at the U.S. Supreme Court: Arizona petitioner James McKinney, who faces two death sentences stemming from brutal murders nearly three decades ago, was denied a chance at jury resentencing in a 5-4 decision penned by Justice Brett Kavanaugh.

The Arizona Supreme Court had already reviewed and upheld McKinney's sentences by the time Ring was issued, but the Ninth Circuit ordered a new review in 2015 after that court found McKinney's sentencing judge had improperly ignored evidence of his post-traumatic stress disorder.

McKinney argued the new review effectively reopened his case, making him eligible for jury sentencing under Ring. The Arizona Supreme Court, however, affirmed his death sentences in 2018 without involving a jury, finding that a state precedent allowed it to re-review his case on a "collateral" basis, or without technically reopening it.

His appeal of that ruling culminated with last week's majority opinion, in which Justice Kavanaugh and his fellow conservative justices ruled "we may not second guess the Arizona Supreme Court's characterization of state law."

In a dissent joined by her liberal colleagues, Justice Ruth Bader Ginsburg blasted the majority, noting that the Ninth Circuit had called for a "new independent review" and citing to Webster's Dictionary — which defines "new" as "repetition of a previous act."

"Renewal of direct review cannot sensibly be characterized as anything other than direct review," she wrote. "Because Ring controls post-2002 direct review proceedings, I would apply that precedent here and reverse the judgment of the Arizona Supreme Court."

According to Ben Cohen, an attorney at The Promise of Justice Initiative who supported McKinney in an amicus brief, the majority opinion potentially closed the door on jury resentencings for death row prisoners with judge-ordered fates, including an estimated 40 people in Arizona alone.

"The Supreme Court has allowed the Arizona Supreme Court to essentially rubber-stamp findings from the 1990s," Cohen said. "It's indifferent both to the science about brain trauma and to the constitutional principle that a jury should make these determinations."

He added that the 5-4 ruling was particularly remarkable because Justice Neil Gorsuch, an avowed originalist on constitutional law, joined Justice Kavanaugh's opinion despite its apparently non-originalist effect.

"Ring was based on the idea that we had the Sixth Amendment wrong by allowing judges [instead of juries] to sentence people to die," Cohen said. "Having acknowledged that … they're allowing these executions to go forward? I was surprised Gorsuch signed on."

In a statement, Arizona Attorney General Mark Brnovich said the ruling "supported the administration of justice."

"We have an obligation to the victims, their families and our communities to uphold the rule of law and to see that death sentences of convicted murderers are carried out," he said.

The convoluted questions at the heart of McKinney's case date back to his sentencing in 1993, a time when Arizona was one of eight states that permitted or required some form of sentencing by judges in capital cases.

Back then, Arizona's death penalty procedure also included a "causal nexus" rule, which prevented mitigating factors like PTSD from being considered at sentencing if they weren't directly connected to the crime in question.

This procedure disadvantaged McKinney, who suffered PTSD due to what one psychologist called a "horrific childhood."

His mother allegedly locked him and his siblings in closets. And when his father, who had alcoholism, took McKinney and moved in with another woman, McKinney's aunt testified that the kids "never had clean clothes that I ever saw them in." She added that they were forced to share a bedroom with dogs, cats, snakes, a goat and a monkey — a menagerie that "regularly defecated and urinated in the bedroom."

Bullied at school due to his appearance, McKinney dropped out in seventh grade and repeatedly tried to run away from home.

By age 23, he had started committing burglaries, including two that turned deadly in March 1991. In the first, McKinney and his half-brother Charles Hedlund beat and shot a 40-year-old woman in her home, making off with about $120. Two weeks later, the pair killed a 65-year-old man in his sleep and stole his watch, some guns and his car.

Because McKinney's PTSD could not be directly connected to the murders, his sentencing judge did not consider it as mitigating evidence and sentenced McKinney to death. In 1996, the Arizona Supreme Court affirmed the sentence, leading McKinney to file a habeas corpus petition in federal court.

That bid ultimately reached the Ninth Circuit, which ruled in 2015 that Arizona's causal nexus rule had violated his right to have mitigating factors considered at sentencing.

"The Arizona Supreme Court's refusal, as a matter of law, to give weight to [McKinney's] PTSD, requires resentencing," the Ninth Circuit wrote.

But according to the state high court, reweighing the aggravating factors of McKinney's brutal murders against the mitigating factor of his PTSD was a process it could handle on its own, without a jury.

In last week's ruling, the nation's top court agreed with the Arizona justices based on its 1990 Clemons v. Mississippi opinion.

In that case, the Supreme Court allowed Mississippi's high court to independently reweigh the evidence for and against a death penalty after the state court found jurors had relied on unconstitutionally vague factors at initial sentencing.

The Clemons opinion stated that "nothing in the Sixth Amendment requires the jury, as opposed to the appellate court, to impose the death sentence or to make the findings prerequisite to such an imposition after the appellate court has invalidated one of two or more aggravating circumstances found by the jury."

During Dec. 11 oral arguments, Justice Kavanaugh repeatedly asked McKinney's counsel Neal Katyal how the Arizona Supreme Court's 2018 review was any different from the Clemons precedent.

The Hogan Lovells partner and former acting U.S. solicitor general responded that "this court has really changed the rules since Clemons" — a reference to Ring's holding that the Sixth Amendment actually does require juries to find the factors that merit a death sentence.

"We're not talking about some technical violation here or something," Katyal said. "We're talking about the heart of what capital punishment sentencing is all about: the weighing of mitigating and aggravating circumstances."

Katyal did not respond to a request for comment on the ruling. His argument was not unprecedented; in 2005, one Sixth Circuit judge even went so far as to say that Ring "very likely … has overruled Clemons." Nevertheless, Justice Kavanaugh's majority opinion stated that "a Clemons reweighing is not a resentencing" that requires a jury and added a quote from Justice Antonin Scalia's concurring opinion in Ring.

"As Justice Scalia explained, 'the states that leave the ultimate life-or-death decision to the judge may continue to do so,'" Justice Kavanaugh wrote.

--Editing by Aaron Pelc.

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