 He has also sat as the Chair of a North American Free Trade Agreement (NAFTA) Tribunal ("UPS v Canada").In 1961 Keith was admitted to the New Zealand Bar and in 1994 appointed a Queen's Counsel.In 1996 Keith was appointed as a Judge of High Court of New Zealand and the Court of Appeal of New Zealand On 21 May 1998 Keith was appointed to the Privy Council and in 2004 was appointed to the Supreme Court of New Zealand.