 He was killed in an automobile collision on the Queen Elizabeth Way when returning home from the opening of the Royal Winter Fair in Toronto.MacTavish was appointed to the Senate of Canada in June 1963 by Prime Minister Pearson and served in the Senate for five months until the fatal accident.He was a senior partner in the Ottawa firm of Gowling, MacTavish, Osborne and Henderson and was an officer of 34 corporations as well as a member of the Board of Trustees of Queen's University.