Border Patrol? C&E? FAA?
Well, according to a friend of mine who was attached to the OSI for awhile, enough governmental red tape coupled with threats of lengthy background checks(a perhaps a whisper in the ear of the I.R.S.), and most local police will do as they are told. Of course this was back in the late '70s to early '80s, and she reassured me that it was mostly bluster.