sentences:  He was further educated at Trinity Hall, Cambridge, where he graduated with Bachelor of Arts in economics and law in 1938, and with a Master of Arts.From 1939 to 1940, Campbell served in the Royal Artillery Supplementary Reserve, British Expeditionary Force, reaching the rank of Second Lieutenant, and was a Prisoner of War in Colditz Castle from 1940 to 1945.He received the Emergency Reserve Decoration (ERD) in 1996.