The Quebec Court of Appeal announced Wednesday it has dismissed an appeal by Jacques Delisle, who was found guilty last June of first-degree murder.
Delisle, who spent nearly a quarter-century on the bench, is believed to be the first Canadian judge to ever stand trial for murder.
A jury found him guilty in the shooting death of Marie-Nicole Rainville in November 2009.
Delisle, who is in his late 70s, was given a life sentence without possibility of parole for 25 years.
Delisle maintained his wife was in poor health and that her death was a suicide. She died of a bullet to the head.
The Crown argued during Delisle's month-long trial that he killed his 71-year-old spouse because he wanted to avoid a costly divorce and move in with his former secretary, with whom he had been having an affair.
Delisle's lawyer argued there were procedural errors that led to the guilty verdict. But in a 41-page ruling released Wednesday, the province's highest court said the former magistrate failed to show the verdict was unreasonable.
According to its ruling, "the guilty verdict for murder is one that a jury acting judicially could reasonably render" and that "there was sufficient evidence to justify a conviction."
As for the decision to convict on a first-degree murder charge as opposed to a lesser charge, the appeals court ruled that given Delisle was planning a life with his mistress, the verdict was one a jury could reasonably render.
The Crown said it was pleased with the ruling.
"We are very satisfied,'' Michel Fortin, one of the prosecutors in the case, told The Canadian Press. ''It confirms what we felt since the beginning."
Delisle's lawyer, Jacques Larochelle, had also argued that the trial judge had given improper instructions to the jury by not giving enough importance to the ballistic evidence, which the defence used to push its suicide defence.
The appeals court did not retain the argument.
Delisle retired from the bench in 2009, having served as an appeals court justice since 1992. Previously, the longtime magistrate had spent seven years as a Quebec Superior Court justice.
Rainville was handicapped and required constant care. She had been paralyzed on one side by a stroke in 2007 and was recovering from a fractured hip suffered a few months before she died.
She was found dead in the couple's condominium on Nov. 12, 2009.
It was Delisle who called 911 and told police he'd found her with a revolver next to her body. Police originally accepted that theory until they probed further.
Delisle was still behind bars, having failed to secure bail last July while awaiting a ruling on the appeal.
— With files from Pierre Saint-Arnaud in Montreal