Well, procurator turns up in Jackie's list and I agree with ot's point about 'co', following TEd's lead. How about taking the old title of Proctor to give you Coproctors? The fact that could be shortened to Cops may be coincidental… :]

1. Rom. Hist. = procurator 1. Obs.
2. A person employed to manage the affairs of another; an agent, deputy, proxy, attorney: = procurator 2. Obs. or arch. exc. in technical use.
†b. A steward: = procurator 2b. Obs.
c. An agent for the collection of tithes and other church dues; a tithe-farmer. In full tithe-proctor.

OED2