As I've noted before, the question as to whether someone is better off when armed is very mixed. Twice I've met possible carjackers by just driving away. Nothing happened. Maybe I was lucky. (In one case, the white perpetrator was so stoned on drugs that he couldn't have carried it out.) Piers Morgan is always saying that incidents in Australia stopped after gun control was implemented, but look at what happened Dec. 15. Maybe if the shop owner had been armed, the incident wouldn't have happened. Gun laws just don't seem to keep weapons away from criminals. But they may keep them away from kids and mentally unstable people.
Update: Feb 3, 2015
The idea of a police welfare check is explained in the HBO film "Crisis Hotline: Veterans Press 1" as explained on the Movies blog today.