A parole board denied release Thursday for an Irvine woman convicted of murdering her boyfriend in 1998 because she thought he had been unfaithful, the Orange County district attorney's office announced Friday.

Judy Diane Valot, 54, is serving 15 years to life at the Central California Women's Facility in Chowchilla for second-degree murder.

Eight members of the family of victim Peter Theriault attended the hearing to oppose freeing Valot, who killed him weeks before Christmas and used her pickup truck to dispose of the body.

"After the inmate brutally murdered him for her obsessive, irrational and wholly incorrect belief he was engaged in another relationship with another woman, she then dumped his body somewhere in the desert near Blythe," the Orange County district attorney's office wrote to oppose Valot's release.

She and her then 13-year-old daughter were living with Theriault in Irvine in 1998 when Valot began suspecting that he was having an affair with a coworker.

That December, shortly after booking tickets to visit his mother for Christmas, Theriault didn't show up for work.

After Theriault's boss forced Valot into filing a missing persons report, police found traces of Theriault's blood in the couple's apartment and the back of her pickup truck.

Valot has maintained her innocence throughout three trials and her incarceration.

That claim to innocence despite two guilty verdicts damages Valot's credibility to the point that she is not suitable for parole, the board decided.

Valot has refused to reveal the location of the body, which was never found.

Her next parole hearing will be in 2020.

jeremiah.dobruck2@latimes.com

Twitter: @jeremiahdobruck