Paul and Mary Jane Taylor, both of Nampa, were found dead Sept. 14, 2017, in a shed at their residence in the 1900 block of West Flamingo Avenue.
Their cause of death was found to be blunt force trauma to their heads. Jane Taylor was also stabbed up to 12 times.
Police and prosecutors say their son, William Taylor, murdered them.
Attorneys on Tuesday morning delivered opening statements in William Taylor’s trial.
William Taylor is facing first-degree and second-degree murder charges in connection with his parents’ deaths.
The Idaho Press reports, Taylor’s jury trial is expected to last at least two weeks.