Closing arguments are scheduled to begin Wednesday in the trial of a Phoenix man accused of sexually attacking and fatally stabbing two young women in separate killings about 30 years ago.

Bryan Patrick Miller is charged with two counts each of first-degree murder, kidnapping and attempted sexual assault.

The double murder trial began in early October and prosecutors said the state is seeking the death penalty if Miller is convicted.

Miller, 50, waived his right to a jury trial so a Maricopa County Superior Court judge will decide his fate.

Miller did not testify and used an insanity defense.

He's accused of killing Angela Brosso in November 1992 on the eve of her 22nd birthday and 17-year-old Melanie Bernas in September 1993.

LORI VALLOW TRIAL: WHAT TO KNOW ABOUT 'CULT MOM' ACCUSED OF KILLING 2 KIDS, HUSBAND'S EX-WIFE

Arizona Fox News graphic

The closing arguments in the trial of a Phoenix man who has been accused of murders.

CLICK HERE TO GET THE FOX NEWS APP

Brosso and Bernas both disappeared while riding their bicycles along the Arizona Canal in north Phoenix, according to authorities.

Police believe the killer knocked Brasso off her bicycle, stabbed her and dragged her off the trail. Her naked body was found decapitated near a bike trail.

Ten months later, police said Bernas’ body was discovered floating in the canal. Bernas was not decapitated, but her bicycle was missing.

Authorities said DNA evidence collected in the aftermath of both crimes showed the attacks were linked to the same suspect and Miller was arrested for the murders in January 2015.

According to police, Miller denied any involvement although he acknowledged living in the vicinity of the killings at the time and said he rode his bike on paths in the area.

It took years before Miller was found mentally competent to stand trial.