Off duty lapel badge of a Constable of the Swansea County Borough Police. The Police War Reserve (PWR) was introduced in 1939. At the height of World War II, in 1944 there were 17,000 War Reserve Constables in the UK. The rank was dissolved on 31 December 1948, causing 686 officers to be discharged from service, and the remainder being recruited for service as a Regular or Special Constable