Why? He came to the police station to commit the shooting so they would be there to, among other things, pick his firearm after the fact. This demonstrates that he had some idea of civic responsibility, and how would this aspect mesh with "serious psychosis"? Messed up he was, true, but more than that?
Oh, so you say "maessed up" and the docs said "depressed."
I say something else was going on.
I have had full repsonsibility of raising 4 sons after my husband died. We've had serious financial difficulties and numerous other problems in these last 7 years, and I'm sure if I could afford a doctor's visit today, I would walk away with an anti-depression prescription. Never have my children ever been in danger of being murdered by their mother.