Lieutenant-Colonel Sir Ranulph Robert Maunsell Bacon QPM (6 August 1906 – 30 March 1988) was a British police officer.

Bacon was born in Westgate-on-Sea, Kent, and educated at Tonbridge School and Queens' College, Cambridge.

[1] Finally in May 1940 he was commissioned into the British Army as a provost marshal on the General List.

In 1947, he returned to Britain as chief constable of the Devon County Constabulary, and held the post until his appointment as assistant commissioner "A" (operations and administration) of the Metropolitan Police on 1 November 1961.

[6] At a press conference on 31 December 1964, he urged the public to "have a go" if they saw an armed robbery taking place, which was criticised as irresponsible by many.