Green’s Dictionary of Slang

license v.

(UK Und./police) for the police to tolerate a given crime, e.g. prostitution or drug-dealing, in return for bribes.

[UK](con. 1960s) A. Frewin London Blues 32: The local drug squad is up to no good — you know, licensing dealers, selling off seized quantities, fitting up people.

In compounds

license money (n.)

(UK Und./police) regular bribes given to the police by major criminals to ensure the smooth running of their operations.

[UK](con. 1960s) A. Frewin London Blues 61: The bent coppers who take weekly ‘contributions’ from all of the bigger villains in London. It’s known as ‘licence money’.