He undertook a wide range of civil legal work, but his practice concentrated mostly on wills, trusts and estates.
Supporting Ian Fraser QC (later Lord Fraser of Tullybelton), he was junior counsel to Margaret Campbell, Duchess of Argyll, from 1959 to 1963 in the notorious divorce action brought by her husband, Ian Campbell, 11th Duke of Argyll, alleging her adultery, which broke new ground in the law of confidentiality.
He was part-time Sheriff Principal of Fife and Kinross from 1971 to 1974, resigning to continue his legal practice when the position became full-time.
He became a Senator of the College of Justice in Scotland in 1979, taking the judicial courtesy title Lord Jauncey.
He was appointed to the Privy Council and was created a life peer with the title Baron Jauncey of Tullichettle, of Comrie in the District of Perth and Kinross.
He was chairman of the House of Lords Committee in 2001-2 that investigated the crash of the RAF Chinook helicopter ZD576 in the Mull of Kintyre in 1994 that killed all 29 on board.
[2][3] He was also a member of the Historic Buildings Council for Scotland from 1972 to 1992 and he was chairman of the influential Edinburgh conservation body the Cockburn Association from 1975 to 1978.