Martin John McLaren was the son of the Hon. Francis McLaren MP and Lady Freyberg GBE, the daughter of Sir Herbert Jekyll. He was born on 11 January 1914 and was educated at Eton, at New College, Oxford and as a Henry Fellow at Harvard. He became an assistant principal at the Home Office in 1938, but joined up in 1939. He served with the Grenadier Guards throughout the war, reaching the rank of Major. In 1943 he married Nancy Ralston. They had three sons, one of whom died young.
McLaren returned to the Home Office as a Principal in 1945, but resigned from the civil service two years later and qualified at the Middle Temple as a Barrister-at-law in 1948. He was adopted for Bristol NW late in 1956, moved into the area and assiduously nursed the seat for the next three years.
He was elected for Bristol NW in 1959 and was brought into the Whips' Office as an assistant Whip in 1961. He became a Lord Commissioner of the Treasury in November 1963 and continued to serve as a Whip after the Government's defeat in the 1964 General Election. However, he lost his own seat two years later. He chose to stay with it, turning down a number of offers in the meantime, and was re-elected in June 1970. He served Alec Douglas- Home as PPS for the term of Heath's Government. He retained the seat in the subsequent General Election, but lost it again in October 1974. He attempted to introduce legislation in 1960 to make local councils liable for accidents that happened because they had not repaired roads, introduced a bill in 1965 to compel the attendance of witnesses and also attempted to reform the libel laws in relation to the press.
He was a director of English China Clays Ltd, joining the Board in March 1973, Archway Unit Trust Managers Ltd and St Helen's Investment Co Ltd.
He had obtained a half blue for squash at Oxford and retained his love for the game. He enjoyed the music of Johann Sebastian Bach and the study of old buildings.
He died on 27 July 1979.