Let’s make one thing clear from the outset. Old Bill has nothing to do with an invoice you haven’t paid yet.

History By the Yard (here) notes that the slang phrase “Watch Out!  Old Bill’s about!” was in use in Covent Garden in 1968, and “Old Bill” was used in Maidstone in 1966. 

Per Wikipedia: The custodian helmet used by the Metropolitan Police Service in London.

However, it is probably much older than this.  It is now commonly used as a slang phrase referring to the police, certainly made more familiar to the general public by the TV series “The Bill” about the police. It does not appear in the comprehensive Slang Terms and Criminal Jargon in The Book for Police published by Caxton in 1958 whereas Partridge’s Dictionary of Slang dates it from the 1950s or ‘perhaps earlier’. The Official Encyclopedia of Scotland Yard (by Martin Fido and Keith Skinner) offers several possibilities for the origin of the phrase (the origin probably being distinctly different from when it came into common use): 

  1. Old Bill referred to King William IV who came to the throne in 1830, a year after the founding of the Metropolitan Police.
  2. The Custom of the Century a play of 1619 by John Fletcher has constables of the watch refer to themselves as “us peacemakers and all our bill of authority”.
  3. Old constables of the watch were sometimes nicknamed for the bills or billhooks they carried as weapons.
  4. Kaiser Wilhelm I of Prussia (Kaiser Bill) visited England about the time that police adopted the current shaped helmet in place of a top hat in 1864 and this association may be relevant.
  5. The ‘old bill’ was in Victorian times a bill presumed to be presented by the police for a bribe to persuade them to turn a blind eye to some nefarious activity.
  6. New laws for the police start their life as bills in Parliament.
  7. ‘Old Bill’ might refer to the music hall song “Won’t you come home, Bill Bailey” also referring to the Old Bailey court.
  8. In the 1860s a popular Sergeant Bill Smith at Limehouse was asked for as ‘Old Bill’.
  9. Many police officers did wear authoritarian looking ‘Old Bill’ moustaches like Bruce Bairnsfather’s famous WW1 cartoon character, the wily old soldier in the trenches. 
  10. In 1917, the government adopted Bairnsfather’s cartoon character in posters and advertisements putting over wartime messages under the heading ‘Old Bill says..’ and for at least some of these, the figure was dressed in Special Constable’s uniform.
  11. The original vehicles used by the Flying Squad had registration plates with the letters BYL.
  12. The London County Council at one time registered all police, fire and ambulance vehicles with plates including letters BYL.
  13. According to the late author and politician Robin Finlayson Cook, ‘old bill’ is a racing term for an outsider or unknown quantity; hence a dodgy prospect for an illegal gambler’s point of view.
Martin Pollins
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