MacDonald was admitted to the Bar of Prince Edward Island in 1962. In the 1970s, MacDonald worked for a firm named Foster, MacDonald & Carruthers. At this time MacDonald also served as Secretary-Treasurer for the Law Society of Prince Edward Island.
MacDonald retired in August 2001. Kenneth R. MacDonald continued to do interviews and discuss legal issues in the media following his retirement.
Notable trials
In 1980, Kenneth R. MacDonald judged MacKinnon v Hashie which has been cited in numerous subsequent cases.
In 1992, MacDonald judged Kane v Canadian Ladies Golf Association, in which Canadian professional golfer Lorrie Kane was permitted to participate in a tournament despite the golf association's former decision that Kane could not participate.
↑Cartwright, William B., ed. (1969). "Barristers and Solicitors in Prince Edward Island". The Canadian Law List. Agincourt, Ontario: Canada Law Book. p.914. OCLC647954180.