They all but have blamed the escalation on Chicago's Aviation Police. In the plea to save documentation and evidence they have done so for at least United, Republic and the City of Chicago. They are not really outsourced, they are real City of Chicago employees. Just not the Chicago (FOP) Police. I'm not sure how much you have witnessed here in the states. We have all sorts of 'police' law enforcement. Aviation Police, Rail Police, State Police, County Police, Municipal Police, Military Police, University Police, Dear Lord the list goes on. This particular group, the Aviation do not even carry guns which has been debated a great deal over the last few years, Pro's and Con's. My understanding, they want guns. After this...not likely to happen soon.