Burns was admitted to the Faculty of Advocates in 1977 and became a Queen's Counsel in 1991.
Before admission, he worked as a legal assistant in New York and California.
During the Lockerbie trial (2000–2002), Burns was one of the advocates representing Abdelbaset al-Megrahi.
Burns served as a temporary judge from 2002 to 2005, and he became a part-time sheriff in 2007.
On 1 June 2012, it was announced he had been appointed a Senator of the College of Justice,[2] and he took up the post on 12 July 2012.