In 1977, John Williams enrolled in the Bachelor of Arts Honours Program at St. Thomas More College at the University of Saskatchewan. He was admitted to the College of Law in 1980 and graduated in 1983 with an Honours degree in Political Science and a Bachelor of Laws.

He articled as a law clerk to the Honourable E.D. Bayda, Chief Justice of Saskatchewan. In 1984, he was called to the Bar. He joined the predecessor to the firm Rath Johnson Hart, becoming a partner in 1990 and, after a merger in 1997, a partner with Gerrand Rath Johnson, where he currently practices.

As a member of the Canadian Bar Association, he has served two terms as Chair of the South Criminal Justice Section for Saskatchewan and five years as a member of the Provincial Council.

In 1995, he organized the South Saskatchewan Association of Criminal Defence Lawyers and served as its president. He is a member of the board of the Canadian Council of Criminal Defence Lawyers and serves as its secretary.

Mr. Williams is a member of Christ the King Church and has served as its music coordinator and a committee member since 1996. He also coached with Hockey Regina with South Regina Community Soccer.

Mr. Williams and his wife Suzanne have four children: David, Thomas, Carolyn and Janine.