Im Jahre 1944 wurde er Richter am High Court und schon 1948 an das Court of Appeal berufen, das zweithöchste Gericht für England und Wales. ###>Denning became a judge in 1944 with an appointment to the Probate, Divorce and Admiralty Division of the High Court of Justice and was made a Lord Justice of Appeal in 1948 after less than five years in the High Court.