WASHINGTON (AP) — No one on the Supreme Court objected publicly when the justices voted to let Arizona proceed with the execution of Joseph Wood, who unsuccessfully sought information about the drugs that would be used to kill him.

Inmates in Florida and Missouri went to their deaths by lethal injection in the preceding weeks after the high court refused to block their executions. Again, no justice said the executions should be stopped.

Even as the number of executions annually has dropped by more than half over the past 15 years and the court has barred states from killing juveniles and the mentally disabled, no justice has emerged as a principled opponent of the death penalty.

This court differs from some of its predecessors. Justices William Brennan and Thurgood Marshall dissented every time their colleagues ruled against death row inmates, and Justices Harry Blackmun and John Paul Stevens, near the end of their long careers, came to view capital punishment as unconstitutional.

“They’re all voting to kill them, every so often. They do it in a very workmanlike, technocratic fashion,” Stephen Bright, a veteran death penalty lawyer in Georgia, said of the current court.

Wood’s execution on July 23 was the 26th in the United States this year and the third in which prisoners took much longer than usual to die. Wood, convicted of killing his estranged girlfriend and her father, was pronounced dead nearly two hours after his execution began, and an Associated Press reporter was among witnesses who said Wood appeared to gasp repeatedly, hundreds of times in all, before he died.

Justice Ruth Bader Ginsburg said she and her colleagues are aware of what happened in Arizona, though she declined to say how the court would rule on a plea to stop the next scheduled execution — of Michael Worthington on Wednesday in Missouri.

“Your crystal ball is as good as mine,” she said last week in an interview with The Associated Press.

The court’s rejection of Wood’s claim that he was entitled to learn more about Arizona’s procedures and the source of the execution drugs came at the end of protracted legal wrangling. A federal judge in Arizona initially denied Wood’s claim. The federal appeals court in San Francisco then granted a reprieve. But the justices reversed that ruling in a brief order. The court said the judge who initially ruled against Wood “did not abuse his discretion.”

In death cases, the court often is the last stop for inmates seeking a last-minute reprieve. They rarely succeed, a function of the need for five votes on the nine-justice court and the reluctance of appellate judges to disturb lower court rulings unless they are demonstrably wrong.

The substance of capital punishment issues usually finds its way in front of the justices when there is no time pressure. In January, the court heard arguments in a case over a Florida law that used a rigid threshold in intelligence test scores in cases of borderline mental disability.

In late May, a five-justice majority led by Anthony Kennedy struck down the law because it “contravenes our nation’s commitment to dignity.”

The soaring language that Kennedy often favors in his opinions has led some death penalty experts to believe that he eventually will provide the fifth vote, along with those of the court’s four liberal justices, to end or severely restrict the use of the death penalty.

“It is impossible to reconcile that language with the secrecy surrounding lethal injections,” said Sherrilyn Ifill, president and director-counsel of the NAACP Legal Defense and Educational Fund. “My assumption is quite a lot is happening behind the scenes.”

Ginsburg cautioned not to read too much into the absence of public dissent when the court rejects 11th-hour appeals to stop executions. “When a stay is denied, it doesn’t mean we are in fact unanimous,” she said.

Still, Ifill said the court’s unwillingness so far to deal with states’ reluctance to reveal much about the provenance of lethal injection drugs is troubling.

“I’m disappointed after all the revelations that at least some justices weren’t prepared to say something pretty strong,” she said.

In 1972, the court struck down existing death penalty laws across the country but did not declare capital punishment unconstitutional. Four years later, the justices approved several rewritten state laws, and executions soon resumed.

Since then, 1,385 inmates have been executed in 34 states. But more than a third of those were in Texas alone, and in recent years, only a handful of other states have carried out executions on a somewhat regular basis, among them Arizona, Florida, Georgia, Missouri, Ohio and Oklahoma.

The number of death penalty prosecutions also has been dropping, in large part because of the availability of lifetime prison sentences with no possibility of parole.

With the number of executions below 50 each year beginning in 2010, the chances of being put to death for killing someone is akin to being struck by lightning, said University of North Carolina political scientist Frank Baumgartner.

“It is hard to argue that the death penalty is much of a deterrent when we’re having 15,000 to 20,000 homicides a year and 30 to 40 executions. The likelihood of being executed is so low that it calls into question the purpose of it,” Baumgartner said.

So far, however, the Supreme Court continues to allow death sentences to be carried out despite problems with execution drugs and a rising number of exonerations through the use of DNA evidence.

And no one on the court is leading the charge against capital punishment the way Justice Arthur Goldberg did in 1963, said Evan Mandery, whose book “Wild Justice” chronicled the effort to abolish the death penalty, its near success in 1972 and the reinstatement of capital punishment four years later.

“Goldberg said, ‘Let’s really advance this up the agenda,'” said Mandery, a death penalty expert at the John Jay College of Criminal Justice in New York. Today, he said, “the court appears happy not to be confronted with the issue.”

One reason may be that some justices believe that problems with the death penalty plague the criminal justice system more generally, he said.

“If your chain of reasoning is that the death penalty is arbitrary and therefore unconstitutional, why are other long prison sentences not unconstitutional. If anything, the noncapital system is more arbitrary,” Mandery said.

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