The trial of Alvaro Rafael Castillo, 22, of Hillsborough started this week.
Castillo was arrested in Aug. 2006 after police said he opened fire at Orange High in Hillsborough. Castillo, 19 at the time, is charged with fatally shooting his father, Rafael Castillo, in their home in Hillsborough on Aug. 30, then driving to Orange High and opening fire.
Castillo has pleaded not guilty by reason of insanity to the charges, which include first-degree murder.
The trial is expected to last at least through this week.