I don't support 'assholes carrying concealed or gang bangers with assault weapons' either, but there has to be a way to stop them, without stopping the legal gun owners as well.
http://usnews.msnbc.msn.com/_news/2012/02/25/10503430-da-mass-cop-shoots-police-officer-returns-to-scene-and-kills-self
BEVERLY, Mass. -- An off-duty police sergeant shot a police officer from a nearby town in Northeastern Massachusetts Friday night, then returned to the scene and killed himself as authorities closed in, the local district attorney said.

What is the point of rules that are not enforced?