Stewart followed a traditional career at the Bar, serving as an Advocate Depute from 1959 to 1964 and Home Advocate Depute from 1970 to 1972. He also served two non-consecutive years on the Criminal Injuries Compensation Board, from 1969 to 1970 and 1976 to 1977.[2]
Stewart married Naomi Joan Douglas in 1955 and had a son and a daughter. He was widowed in 2005. He lived in Edinburgh and was a member of the New Club.[2]
He is buried with his wife in Dean Cemetery in western Edinburgh. The simple grave lies in the group of modern stones where the original cemetery links to its north Victorian extension.