William received a Bachelor of Fine Arts degree in 1976 and a Master of Fine Arts degree in 1979 from the University of British Columbia. In 1983 he obtained his LL.B. from McGill University and then attended the University of Saskatchewan as a University Scholar.
William articled with DeBou, Wood and Company and was called to the Bar of British Columbia in 1986. Since that time he has worked in Alberta and British Columbia in aboriginal law, administrative law and criminal law. In 1992, he was appointed to the British Columbia Review Board, where he worked as Registrar and Counsel.
Since 1997 William has worked extensively on the development of Paralegal Distance Education courses for the University. He also gives seminars to lawyers and adjudicators on legal writing, business law and aboriginal law. In 2009 and 2010, William was a Visiting Professor at Kushiro Public University of Economics in Kushiro, Japan. During the 2011-12 academic year, William was on educational leave at Hebrew University, Jerusalem, and in Osaka, Japan.