The lawyer, soldier and academic Thomas Broun Smith was born on 3 December 1915. He was the son of J. Smith, DL. JP, and Agnes Smith, of Symington, Lanarkshire. He was educated at the High School of Glasgow, and at Sedbergh School, and then he studied at Christ Church, Oxford, where he was awarded a First Class Honours degree, an MA, in 1937, and an Eldon Scholarship. Smith was called to the English Bar (Gray's Inn) in 1938.

Prior to his call to the Bar, he had signed up with the Territorial Army in 1937, and so his period as a pupil in chambers was cut short by the start of war in 1939 and active service. During the Second World War he served with the British Expeditionary Force (BEF) and with the Home Forces, and he was in the Middle East and the Central Mediterranean. He took part in the retreat to Dunkirk. By 1945 he was a Lieutenant-Colonel in the Gordon Highlanders and had been mentioned in despatches. Between 1946 and 1947 he had been attached to the Foreign Office. During the war, in 1940, he had married Ann Dorothea Tindall of Exmouth in Devon.

Smith had been admitted to the Faculty of Advocates in Scotland in 1947, taking silk in 1953. In 1949 he was appointed to the Chair of Scots Law at Aberdeen University where he was twice Dean of the Faculty of Law. He was awarded a DCL (Oxford) in 1956. Then, in 1958 Professor Thomas Broun Smith Q.C., D.C.L. was appointed to the Chair of Civil (Roman Law) at Edinburgh University in succession to Professor M. G. Fisher who retired in September 1958. Also in 1958 he became the first Scots lawyer to be elected a Fellow of the British Academy. Between 1954 and 1970 he was a member of the Scottish Law Reform Committee.

Professor Smith was awarded a LL.D (Edinburgh) in 1963, and he was also awarded an Honorary LL.D (Cape Town), and honorary degrees from Glasgow and Aberdeen. He was made a Knight Bachelor in 1981 in recognition of his services to the Law of Scotland. His publications included: Doctrines of judicial precedent in Scots Law (1952), The development of the laws and constitution of Scotland (1955), British Justice: The Scottish contribution (1961), A short commentary on the law of Scotland (1962), Property problesm in sale (1978), and Basic rights and their enforcement (1979).

Sir Thomas Broun Smith, QC, FBA, FRSE died on 15 October 1988.