In January 1999, van der Westhuizen joined the High Court bench as a judge of the Transvaal Provincial Division and an appointee of President Nelson Mandela.
[5] In addition to serving as counsel in human rights litigation,[5] he frequently represented film distribution companies in appealing the apartheid government's censorship decisions.
[5][8] On 1 January 1999,[9] President Nelson Mandela appointed van der Westhuizen to the bench as a judge of the Transvaal Provincial Division of the High Court of South Africa.
"[4] On 7 January 2004, following consultation with the Judicial Service Commission, President Thabo Mbeki announced that van der Westhuizen would be elevated to the Constitutional Court of South Africa.
[10] He joined the apex court on 1 February 2004;[2] he and Thembile Skweyiya filled the vacant seats left by retired justices Laurie Ackermann and Richard Goldstone.
[1] Van der Westhuizen retired from the judiciary on 29 January 2016 at a special ceremonial session during which he handed down his final opinion, a unanimous judgment in Tronox KZN Sands (Pty) Ltd v KwaZulu-Natal Planning and Development Appeal Tribunal and Others.
[4] During the ceremony, he joked that his legacy in the court would be that "I was the first judge to bring The Great Gatsby, President John F. Kennedy, Monty Python, Kris Kristofferson and Bob Dylan into our constitutional jurisprudence.
"[4] In July 2017, after a prolonged delay,[11] President Jacob Zuma appointed Leona Theron to fill van der Westhuizen's seat on the Constitutional Court bench.
[12] On 1 April 2016,[13] van der Westhuizen succeeded retired justice Thembile Skweyiya as the Inspecting Judge of the Judicial Inspectorate for Correctional Services.