Jacques Larochelle said he believes his client Jacques Delisle is the victim of a miscarriage of justice and is innocent.
"I am absolutely convinced," Larochelle said Thursday.
Larochelle told The Canadian Press he wants trial evidence pertaining to ballistics to be reviewed by an independent person or group and then presented to Justice Minister Peter MacKay.
The Criminal Code allows a justice minister to order a new trial or refer the case to an appeals court if he or she has reasonable grounds to believe a miscarriage of justice has occurred.
Larochelle said he believes the complex ballistics evidence in the case was not analyzed correctly.
He said an analysis of the wound caused by the bullet and powder residue on the victim's hand does not suggest a murder.
"The testimony by the experts for the Crown under cross-examination and otherwise clearly establish ... that the murder was scientifically impossible and suicide is the only possible answer."
He added that "the weakness of a jury in assessing scientific evidence is notorious."
That was why Larochelle said he requested a trial by judge alone, although the Crown objected to that request.
MacKay's office had no comment on the request, although spokeswoman Paloma Aguilar noted the Supreme Court of Canada recently refused to hear an appeal by Delisle.
Delisle spent nearly a quarter-century on the bench, in Quebec Superior Court as well as the Quebec Court of Appeal. He is believed to be the first Canadian judge to stand trial for first-degree murder.
He was sentenced in 2012 to life in prison for the fatal shooting of his 71-year-old wife.
Delisle said his wife, who was depressed and paralyzed after a stroke, killed herself with the gun found next to her lifeless body.
The Crown argued that Delisle killed his wife to get rid of her and avoid a costly divorce.
The Quebec Court of Appeal upheld the guilty verdict last year.
Larochelle said Delisle's case is "a terrible, horrible failure of our justice system."