He was the unsuccessful Liberal Party parliamentary candidate for the Unionist seat of Ayr Burghs in 1918 where the intervention of a Labour Party candidate prevented what would otherwise have been a rare gain for the Liberals;
He entered Parliament as Liberal MP for Aberdeenshire Central at a by-election in April 1919. This was a notable gain for the opposition Liberals against a Unionist candidate supported by the Coalition Government;
He served as the Scottish Liberal Whip from 1923 to 1924.[12] At the following general election, a Labour candidate intervened and split the anti-Unionist vote, which cost him his seat;
In 1931, following the formation of the National Government, he was returned unopposed at the general election as a supporter of the new administration. He was an unpaid Assistant Government Whip from 1931 to 1932. When the Liberal party left the National Government he continued in the role of Scottish Liberal Whip from 1932 to 1934. In 1935 he was defeated at Banffshire;
^ ab'WOOD, Major Sir Murdoch McKenzie', Who Was Who, A & C Black, an imprint of Bloomsbury Publishing plc, 1920–2007; online edn, Oxford University Press, Dec 2012; online edn, Oct 2012 accessed 22 April 2014