Use his own words against him...
"While there is no law, or set of laws, that can prevent every senseless act of violence completely, no piece of legislation that will prevent every tragedy, every act of evil, if there’s even one thing we can do to reduce this violence, if there’s even one life that can be saved, then we’ve got an obligation to try,"
Sounds like a "These laws wouldn't have done any good, but I'll force them on you anyway."
We can save lives by getting inner city gang-bangers off the streets and mental health professionals back to actually TREATING patients instead of just giving them meds and sending them home.