 A frequent visitor to the High Court, where he often appeared in constitutional cases, Louat was the only practising doctor at the New South Wales Bar for many years.He was president of the Constitutional Association of New South Wales from 1940 to 1946 and spent much of World War II defending civil liberties and free speech.In 1950, he was nominated as an observer for the 1950 referendum in the French territories in India by the Court of International Justice.