A 79-year-old Nevada prison inmate who was sentenced in 2010 to die may get a chance to again argue he's not guilty, after a judge in Las Vegas overturned his conviction and granted him a new trial.

However, the judge on Thursday postponed setting a new trial date for John Matthias Watson III, after prosecutors appealed the ruling to the Nevada Supreme Court.

Watson's attorney, Jamie Resch, says Watson's trial lawyers made colossal errors.

Everilda Watson's body was never found and John Watson, a retired math teacher from Ontario, California, always maintained that he didn't kill her.

But in a bid to spare him from death row — and without his consent — one of his lawyers told jurors that Watson might have been guilty of a lesser murder charge.