He served as a Judge of the Chancery Division of the High Court of Justice between 1937,[2] when he was knighted,[3] and 1944.

In the latter year he was appointed a Lord of Appeal in Ordinary,[4] sworn of the Privy Council and created a life peer as Baron Simonds, of Sparsholt in the County of Southampton.

He was holder of the office at the time of the Coronation of Queen Elizabeth II, adding a major ceremonial role to his judicial one.

[5] In June 1952 he was made a hereditary peer as Baron Simonds, of Sparsholt in the County of Southampton.

In 1962 Simonds achieved some notoriety in the case of Shaw v DPP,[8][9] where the House of Lords created what was, in effect, a new criminal offence of "conspiracy to corrupt public morals".