Scotland Yard 1940's/1950's. in Great Britain: Mervyn Mitton's British & Colonial Police Forces Posted October 31 · Report reply My May 1929 bible of Scotland Yard identifies 'A' Department was for Administration. A3 covered Promotions & Transfers, Pay Rates, Ceremonials, Special Duties, Medical & Sick, Police Orders. Previously called the Executive Branch A3 was mainly clerical duties, but also included Constables attached to Scotland Yard for special purpose such as motor drivers, and wireless operators. It also included the telegraph office.