What the hell else are they gonna do? Their whacked out kid just went on a killing spree.
Well they could have said it was partly their fault for raising someone that thought it was a good idea to kill a bunch of people because he wasn’t handed willing women.
Most likely the result of absent parenting, then bribery of stuff for his attention or decent behavior.
Perhaps they could have spent the money they paid for his car on some mental health treatment.