So how does the 'Mayor' or anyone secure his property against a gangbanger with a gun beyond having two off duty cops bounce? Move to Denver, so you can pay for the suit.
One thing he could do is not hire illegal aliens who can commit murder, then flee to Mexico where they won't be prosecuted. Another thing he could do is ask a little about the background of this guy before he hired him.
You don't seem to realize how completely the Mayor was involved in this. His business hired the guy who got killed, and it hired the guy who committed the murder. If he weren't Mayor, the lawyers would be all over him.