Vigilante street patrols with vehicles made to look like marked and unmarked police vehicles, often under the guise of being affiliated with a volunteer ambulance service:
I shouldn't even respond to this, because it can only cause problems, but really...
Hollywood? NY Diamond trade?
I don't really have a problem with them (not being in those industries), but that someone in the US could be unaware is bizarre.
Read the history section.
Vigilante street patrols with vehicles made to look like marked and unmarked police vehicles, often under the guise of being affiliated with a volunteer ambulance service:
http://privateinvesigations.blogspot.com/2011/07/williamsbur...
http://gothamist.com/2010/06/05/pedestrian_struck_by_volunte...