nope, at least as far as i know he wasnt. this school shooting doesnt make up shit for the number of gun deaths we have in the US though. we have around 12,000 gun related homocides per year, over 80% of those being from gang members career criminals or felons.
our extremely high numbers are a result of our absurd gang problem for the most part, with criminals and felons helping out quite a bit as well.
by felon i meant convicted felon, as in out of jail, cant purchase a gun legally anyway.
as for these school shootings, a lot of them seem to be kids taking their parents gun and going on a rampage. a lot of them including columbine were more planned out, acquired the right guns beforehand crimes. but we have a huge surge in kids grabbing their parents guns and going on shooting sprees and i honestly dont know how you stop that. the kids themselves are the root of the problem, this is something thats only started happening in the last 10 years or so, gun laws havent changed so what the hell has?
and the better question is how do you fix it?
these school shootings make up a very very small number of gun deaths per year nationwide, so as sad as they are, we have bigger problems when it comes to gun crime and thats gangs and illegal gun trade.