The US Supreme Court on Monday dismissed the appeal of Georgia death row inmate Troy Davis, whose loud and persistent claims of innocence attracted the support of death penalty opponents around the world and forced a series of extra hearings to investigate his case.

In the end, court after court rejected his pleas.

On Monday the high court, without comment, dismissed three appeals filed on Mr. Davis’s behalf.

The action opens the way for Georgia authorities to set an execution date.

Davis was convicted and sentenced to die for the 1989 shooting death of off-duty Savannah Police Officer Mark MacPhail. He’s been on death row since 1991.

He has avoided execution dates three times by persuading a new court to examine his case. But the high court’s action on Monday may have brought his appeals to an end.

In 2009, Davis’s lawyers persuading the US Supreme Court to take the highly unusual step of ordering a federal judge to reexamine Davis’s case from top to bottom.

The court took the action after lawyers presented affidavits claiming that seven of nine witnesses at Davis’s trial had recanted their testimony.

After conducting a hearing last summer, the federal judge upheld Davis’ murder conviction. “While Mr. Davis’s new evidence casts some additional, minimal doubt on his conviction, it is largely smoke and mirrors,” US District Judge William Moore wrote in a 174-page order.

The central issue in that evidentiary hearing was whether Davis was the person who attacked a homeless man outside a Burger King restaurant in August 1989 and then shot and killed MacPhail when he came to the aid of the homeless man.

The off-duty officer was working as a security guard at the time of the shooting.

With no murder weapon or other physical evidence, state prosecutors relied on eyewitness testimony to build their case. The shooting took place in a darkened parking lot at 1 a.m.

Some witnesses weren’t sure what they saw. Defense lawyers later obtained statements from witnesses contradicting their earlier statements to police.

The contradictions began to attract the attention and comment of capital-punishment opponents and human-rights activists including former President Jimmy Carter, Pope Benedict XVI, Nobel laureate Archbishop Desmond Tutu, and officials at Amnesty International.

Judge Moore examined each of the seven recantations and decided that only one was fully credible. But he concluded that the recantation came from a witness whose testimony at the trial had been “patently false,” and ultimately not important to the conviction.

The judge said two other recantations were partly credible, but they only minimally diminished the state’s case against Davis. The remaining four recantations did not diminish the state’s case at all, the judge concluded.

It wasn’t the first time Davis and his lawyers had failed to convince the authorities of his innocence.

In 2007, amid growing publicity surrounding the Davis case, the Georgia Board of Pardons and Paroles halted Davis’s scheduled execution. The Pardons Board then spent a year studying his claims.

The board released a statement in September 2008: “As part of its proceedings, the Board gave Davis’ attorneys an opportunity to present every witness they desired to support their allegation that there is doubt to Davis’ guilt.”

It added: “In addition, the Board has studied the voluminous trial transcript, the police investigation report and the initial statements of the witnesses. The Board has had certain physical evidence retested and Davis interviewed.”

The statement concludes: “After an exhaustive review of all available information regarding the Troy Davis case and after considering all possible reasons for granting clemency, the Board has determined that clemency is not warranted.”

MacPhail’s mother, Anneliese MacPhail, told the Associated Press she was hopeful Davis’s legal appeals were over.

“I’m relieved that it’s over now,” she said. “Well, maybe. I’m not believing it until it’s over. It’s been going on for so many years now that every time we think we’re near an end, something else comes up. I just want this to end so badly, you won’t believe it. This has been a nightmare.”