Richard Wagner was called to the Quebec Bar in 1980 and practised law until being appointed to the Quebec Superior Court in 2004. He was a partner in the law firm of Lavery, de Billy (formerly Lavery, O’Brien and Lavery, Johnston, Clark, Carrière, Mason & Associés) from 1980 to 2004.
He argued cases before all the Quebec courts and quasi-judicial tribunals, as well as before the Federal Court and the Supreme Court of Canada. He was elected First Councillor of the Bar of Montréal for 2000-2001 before being elected Bâtonnier of the Bar of Montréal for 2001-2002.
On September 24, 2004, Wagner was appointed to the Quebec Superior Court for the District of Montréal, where he sat in the Civil Division, the Commercial Division and the Criminal Division. He was appointed to the Quebec Court of Appeal on February 3, 2011.
Wagner was appointed to the Supreme Court of Canada on October 5, 2012 and appointed Chief Justice of Canada, December 18, 2017.