Tom McNally was part of a small group of MPs, including his predecessor as Liberal Democrat leader in the Lords, Shirley Williams, who broke away from the Labour party in the early 1980s to form the centre left SDP.
McNally had been a high-flyer under Labour Prime Minister James Callaghan, running the political office at Number 10, before entering Parliament in 1979.
He lost his Stockport South seat in 1983 but kept the SDP faith until 1987, when he supported the party's merger with the Liberal Party, going on to spend 10 years as Lib Dem leader Paddy Ashdown's political adviser. He entered the Lords in 1995.
He was a member of the Puttnam Committee on the Communications Bill, where he was a strong advocate of public service broadcasting. Outside politics he has enjoyed a successful career in public relations and is chairman of PR giant Weber Shandwick.