Brian John Barker CBE QC (born 1945) is a British judge and the former Common Serjeant of London, the second most senior judge at the Old Bailey. From February 2013 to January 2015 he served as the Recorder of London, the senior judge at the Old Bailey.
Barker graduated from Birmingham University with an LLB degree in law in 1966. Barker was called to the Bar by Gray's Inn in 1969 and was a leading criminal barrister excelling as a prosecutor and a defender. He served as Chairman of the Criminal Bar Association. He was appointed Queen's Counsel in 1990, and was appointed a circuit judge at the Old Bailey in 2000.
Barker was appointed as the 79th holder of the post of Common Serjeant of London (the second most senior judge at the Old Bailey) in 2005, succeeding Judge Peter Beaumont QC. The Common Serjeant is an ancient office first recorded in 1291 with the appointment of Thomas Juvenal. Barker has since presided over trials including those of Umran Javed, the murderers of Jody Dobrowski, the murder trial of rapper 'Crazy Titch', aka Carl Dobson, and the murder of Ben Kinsella. He succeeded Peter Beaumont as Recorder of London (the most senior judge at the Old Bailey) in February 2013.