Sir Charles Barrie Knight Mantell, PC (30 January 1937 — 1 May 2010) was a British barrister who served as a High Court judge and a Lord Justice of Appeal.
Mantell was born in Romiley, then part of Cheshire, the second son of Francis Christopher Knight Mantell and Elsie, née Caton.
After National Service as an education officer in the Royal Air Force between 1958 and 1961 (reaching the rank of flying officer), he was called to the bar by Gray's Inn and later served at the chambers of Sir Patrick Russell in Manchester.
He practised on the Northern Circuit and was present at the trials of the Birmingham Six, Trevor Hardy and Terry Clark.
He was promoted to the Court of Appeal in 1997 and was sworn of the Privy Council.