riot money

Noun

riot money (uncountable)

1. (obsolete) Additional pay given to soldiers for serving against their fellow citizens, for example in quashing civil disorder.
   • He had learned that the great disturbance amongst a portion of the guards was attributed to the failure in issuing a certain rate of allowance which was called riot money. […] Knowing also, that if they were ordered to march for foreign service no such increased rate of allowance was either given...1820 June 19, T. C. Hansard (publisher), “House of Commons: Military Disturbance” in The Parliamentary Debates, New Series; Commencing with the Accession of George IV, volume 1, page 1147
   • ’Tis all the same,
     He’ll serve instead of riot money, when
     Our murmuring troops bivouaque in Thebes’ streets;
     And January winds, after a day
     Of butchering, will make them relish carrion.1820, Percy Bysshe Shelley, Oedipus Tyrannus; Or, Swellfoot The Tyrant: A Tragedy in Two Acts