 In general, these have taken their lead from the Metropolitan Police Service, due to it being recognised as the first police service in England.The base colour is a very dark blue, almost indistinguishable from black (and recently often is black), which earned the police the nickname of the "boys in blue".The Metropolitan Police officers were unarmed to clearly distinguish them from military enforcers, which had been the system of policing seen before the 1820s.