Richard Wolf

USA TODAY

WASHINGTON — The death of Justice Antonin Scalia has left the Supreme Court divided down the middle on the death penalty at a time when its constitutionality is coming under increased scrutiny.

The justices deadlocked 4-4 late Thursday night over the scheduled execution of an Alabama prisoner who killed a police officer three decades ago. Without Scalia's vote, they could not overrule a state court that had blocked the execution based on the inmate's mental state.

Supreme Court upholds Ala. execution stay

The issue of intellectual disability may return to the court as early as Monday, when the justices could decide whether to hear a case next fall challenging Texas courts' standard for determining mental competency. The state leads the nation in executions with 537 since 1976, including six this year.

The Texas case also raises a more far-reaching issue: whether decades in solitary confinement awaiting execution violates the Constitution's ban on cruel and unusual punishment.

Since Scalia's death in February, the court has deadlocked four times, with more almost certainly to come. The most notable tie vote denied an anticipated victory to opponents of public employee unions who had sought to end mandatory fees from non-members, now required in about half the states.

Although Thursday night's tie vote spared just one man — Vernon Madison, convicted of the 1985 murder of Mobile, Ala., police officer Julius Schulte — it highlighted the justices' deep divide over the death penalty.

That divide prompted an angry exchange from the bench on the last day of the court's term in June, when the justices ruled 5-4 that states could continue to use a controversial sedative as part of their lethal injection protocols. Four justices spoke up — two in favor, two against — and Justice Stephen Breyer said the court should consider the overall constitutionality of the death penalty.

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Breyer raised four issues — the potential for mistakes, racial and other disparities, decades-long delays, and increasing numbers of states and counties abandoning capital punishment. Justice Ruth Bader Ginsburg signed on to his dissent.

"Rather than try to patch up the death penalty's legal wounds one at a time, I would ask for full briefing on a more basic question: whether the death penalty violates the Constitution," Breyer wrote.

Though it was not his opinion or dissent, Scalia spoke from the bench that day to complain about the growing trend. "Maybe we should celebrate that two justices are willing to kill the death penalty outright instead of pecking it to death," he said sarcastically.

Since then, the court has refused to take on a case testing whether capital punishment remains constitutional. But viewing Breyer's dissent as an invitation, lawyers for death-row inmates continue to try.

The Texas case of Bobby James Moore, who shot and killed a grocery store clerk during a botched robbery in 1980, is the latest such effort. His attorneys say Moore's mental competency was gauged using a 23-year-old definition of intellectual disability, rather than current medical standards. They also say his execution after 35 years on death row, largely alone in his cell, would violate the Constitution.

"Prolonged confinement for many decades under sentence of death represents a sword of Damocles perpetually hanging just above the condemned individual’s head," Moore's attorney, Clifford Sloan, argued in court papers.

In response, Texas defended the standard used by its Court of Criminal Appeals and noted that lengthy periods of confinement have much to do with defendants' appeals. "Because any such delay is largely of the defendant’s own making, no court — state or federal — has held that a lengthy stay on death row renders his sentence unconstitutional under the Eighth Amendment," the attorney general's office said.

While Scalia's death gives the court's liberals equal footing on some death penalty questions, the court has been reluctant with only eight members to take on controversial cases. Testing the overall constitutionality of capital punishment would fit that category.

But Justice Anthony Kennedy has switched sides on major cases involving intellectual disability. He voted with the majority in a 2002 Virginia case that ended capital punishment for people with intellectual disabilities, and he wrote a 2014 opinion that barred states from using only a strict IQ standard to determine a prisoner's competency.

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Kennedy also has been the court's most outspoken justice on the issue of solitary confinement. Last year, he told a congressional panel that "solitary confinement literally drives men mad."