Born in Toronto in 1891, Macdonald studied Law at the University of Toronto and Osgoode Hall. He practised law in Brantford, Ontario and served with the Canadian Expeditionary Force in the First World War from 1914 to 1918. In 1921 he married Muriel Whittaker. Macdonald was a Member of Parliament from 1935 to 1953, and served as Minister without Portfolio, Solicitor General, Deputy Speaker and later as Speaker. He became a Senator in 1953 and served as Government Leader in the Senate. Macdonald served as Lieutenant Governor from 1968 to 1974. He was involved with many service groups, such as the Canadian Order of Foresters and the Kiwanis Club. He died in Toronto in 1976.