De Villiers was admitted to the
Middle Temple in January 1893, thereby qualifying for admission to the Johannesburg
Bar, where he began to practise in 1894. After the
Jameson Raid, De Villiers acted as the assistant to
John Wessels, in defending the Reformers in the high treason trial, following the Raid. Shortly after the trial, the
Orange Free State President,
M. T. Steyn appointed him Attorney General of the
Orange Free State, a post he occupied for a short while. He resigned the post in 1898 and returned to the Johannesburg Bar. When the
Second Boer War broke out in October 1899, De Villiers joined the Free State forces and served as legal adviser to general Marthinus Prinsloo. During the
Battle of Bothaville, on 6 November 1900, he was seriously wounded in the front lines when a bullet passed through both of his legs. He was captured by the British and deported to a
POW camp in
Bermuda, where he spent eighteen months. After the war he toured through England, France and Germany before returning to Johannesburg and resuming his practice in 1903. When the
Union of South Africa was formed in 1910, de Villiers was not included in the first Union cabinet but was appointed the first Judge-President of the
Transvaal Provincial Division and also additional Judge of
Appellate Division. He became a permanent Judge of Appeal in 1920 and after the death of Sir
William Solomon in 1929, he was appointed Chief Justice of the Union of South Africa and in 1931 he was made a member of the Privy Council. in 1923 (from left):
Sir John Gilbert Kotzé,
Sir William Henry Solomon,
Sir James Rose Innes (then
Chief Justice), de Villiers and
Sir John Wessels. ==Honours==