A. William Cox was born on 13 May 1921 at Saint John, New Brunswick, the son of Arthur Earle and Anna Beatrice (McGinley) Cox. He attended public schools in Saint John and graduated from Acadia University with a BA in 1942. While at university he served as an officer in the Canadian Officers Training Corps (COTC), and upon graduation was posted to Great Britain. After discharge he studied law at New College, Oxford, before returning to Nova Scotia and entering Dalhousie Law School, graduating with an LL.B. in 1949. He continued to serve in the Canadian Militia, retiring as a Lt.-Colonel. He became a well known trial lawyer and senior partner with Cox Downie from 1963 to 1991. He was a past-president of the Nova Scotia Barristers' Society (1971-1972), Federation of Law Societies of Canada (1975-1976) and Canadian Barristers' Association (1980-1981). He also served as the President of the Saraguay Club, Treasurer of the Nova Scotia Progressive Conservative Party, and Vice-President of the Progressive Conservative Party of Canada. He chaired the Nova Scotia Committee on Implementation of Legal Aid (1971) that led to the introduction of Provincial Legal Aid in Nova Scotia. He also served as a columnist with the Halifax Chronicle-Herald beginning in 1997. He was married to Margaret Macpherson and they had four daughters. He died in Halifax, Nova Scotia on 8 October 2008.