“By the end of next week, we will find out that he was another kid on antidepressants or mood-drugs. Virtually every single one of the teenagers who gone this route...had prescription drugs.”
Maybe, but that has nothing to do with his decision the murder ten people.
The shooter is the only one to blame.
Then why ore there no mass shootings in which the perpetrator(s) were not primed with psychoactive drugs?
Why were there no such shootings before the release of psychotropic drugs to deal with abnormal behaviors?