A Nevada prison inmate who was sentenced in 2010 to die could get another chance to argue he’s not guilty, after a judge in Las Vegas overturned his conviction and granted him a new trial.

However, John Matthias Watson III will have to await the outcome of a Nevada Supreme Court appeal, after Clark County District Court Judge Michelle Leavitt on Thursday postponed a trial-setting hearing to allow justices to review her ruling.

Watson’s attorney, Jamie Resch, said that although Watson, 79, remains on death row, he’s excited to have a chance to reverse what Resch called a colossal error by Watson’s trial attorney.

This undated Nevada Department of Corrections photo shows death row inmate John Matthias Watson III. Prosecutors in Las Vegas are appealing a judge's ruling that the retired math teacher from Ontario, California, should get a new trial on murder and other charges in the death of his wife, Everilda Watson. He was found guilty in 2010 of killing her during a 2006 trip to Las Vegas. Her body has never been found. (Nevada Department of Corrections via AP)
This undated Nevada Department of Corrections photo shows death row inmate John Matthias Watson III. Prosecutors in Las Vegas are appealing a judge’s ruling that the retired math teacher from Ontario, California, should get a new trial on murder and other charges in the death of his wife, Everilda Watson. He was found guilty in 2010 of killing her during a 2006 trip to Las Vegas. Her body has never been found. (Nevada Department of Corrections via AP)

Watson, a retired math teacher from Ontario, California, was found guilty of killing his wife of 34 years during a 2006 trip to Las Vegas.

Everilda Watson’s body was never found, and John Watson always maintained that he didn’t kill her.

“Mr. Watson very much wants a new trial,” Resch said. “He has long felt there were multiple problems with evidence at trial.”

In a bid to spare Watson from death row — and without Watson’s consent — attorney Patrick E. McDonald told jurors during closing arguments of the 2010 trial that circumstantial evidence could lead them to find Watson guilty of a lesser charge of second-degree murder.

Prosecutors had presented blood, gun and DNA evidence suggesting Everilda Watson had been killed; hotel bookings showing that John Watson used an alias; a receipt showing he bought a band saw in Las Vegas; and police reports showing Watson traveled to remote areas in Nevada and California.

A tarp stained with Everilda Watson’s blood was found in a mountain dump in California’s Tulare County and police said Watson had a wig, fake mustaches, cash and a bus ticket to El Paso, Texas, when he was arrested in August 2006.

The jury found Watson guilty of first-degree murder, kidnapping and robbery and sentenced him to be executed. Watson lost previous appeals to the Nevada Supreme Court.

McDonald did not respond to a telephone message on a number affiliated with his former law practice, and an email message was returned.

His law license was suspended in 2013 amid allegations that he misappropriated $480,000 in client funds. The Nevada Supreme Court put him on disability-inactive status in 2015. Disciplinary proceedings against him were suspended.

Watson’s other trial attorney, Stephanie Kice, did not immediately respond to messages about the case. Prosecutor Marc DiGiacomo declined to comment pending state Supreme Court review of Leavitt’s May 9 ruling.

The judge said Watson’s attorney should not have conceded his guilt.

Resch pointed to a key ruling by the U.S. Supreme Court in May 2018 that said a defendant has the absolute right to declare his innocence even if his attorney believes admitting guilt offers the best chance to avoid the death penalty.

Nevada courts have had that rule for decades, Resch said.

“If the defendant wants to assert his innocence the attorney is bound by that,” he said.