I don't really have much to say on the matter, but this has been THE BIG THING on the news since it happened. And also it's relevant to this thread so yeah.
http://www.businessinsider.com/mark-...stimony-2013-1
http://www.businessinsider.com/repor...phoenix-2013-1
Apparently the shooter was in some kind of lawsuit with two of the people shot and the third person was some lady taking pictures who got shot in the hand. At first she thought she got hit with glass that had shattered nearby but that wasn't the case. They focused an awful lot on her hand.
As far as I know they're still looking for the shooter.
Really though, of course this shit is going to happen, especially in Arizona, where you can legally own a gun without having it registered. No background checks no nothing. Just gotta be 18+ and you can walk into pretty much any store here and just buy one.