Alasdair Roderick Mackenzie (3 August 1903 – 8 November 1970) was a Scottish farmer and politician who became a Liberal Party member of parliament.
Mackenzie had been party spokesman in the Commons on Agriculture and Fisheries and posts and telecommunications.
He differed from the majority of his party in opposing United Kingdom membership of the European Economic Community.
He was the lone Liberal voting against the Labour government at the end of debate on the Common Market.
He was a principal supporter of the campaign to re-instate the death penalty for the murder of police or prison officers led by Conservative MP, Duncan Sandys in 1966[1] In 1970 he was appointed to the Scottish Agricultural Advisory Committee but died later that year.