Tom McNally has been a Liberal Democrats peer since 2004.
His biography on the Liberal Democrat Party website reads:
- He was appointed a Parliamentary adviser to GEC (1983-4) and then Director General of the British Retail Consortium (1985-87). In 1987, he joined public relations firm Hill and Knowlton as Director of Public Affairs, before moving to a similar position at Shandwick Public Relations in 1993. He subsequently became Vice-Chairman of Shandwick. In 2003, he was appointed to the new post of non-executive Vice-Chairman of Weber Shandwick following the takeover of Shandwick by American communications giant Interpublic. He left Weber Shandwick in November 2004 on his appointment as Leader of the Liberal Democrats in the House of Lords
Prior to the September 2012 reshuffle
- Departmental business in the Lords
- Support to Secretary of State on constitutional matters
- Human rights and civil liberties
- Freedom of information, data protection and data sharing
- Legislation and law reform
- Public law and public legal issues
- Support to the Secretary of State on EU and international business
- Crown dependencies
- Land Registry
- National Archives
- Law Commission
Lord McNally was the only justice minister to survive the September 2012 Cabinet reshuffle, taking over responsibility for the legal aid portfolio from Jonathan Djanogly. He also acquired shared responsibility for human rights and civil liberties with the Conservative Damian Green, who took over the joint role with the Home Office with responsibility for policing and criminal justice. 
- Fellow of University College London, the Royal Society of Arts, the Institute of Public Relations, and the Industry and Parliament Trust.
- Trustee of the Verulamium Museum, St. Albans, President of the St. Albans Liberal Democrats and a member of the National Liberal Club.
- Former officer of the All-Party Parliamentary Group on Nuclear Energy circa 2007
- Cited as an adviser on this study by Dr Phil Parvin Friend or Foe: Lobbying in British democracy (Jan 2007) ISBN 978 0 900423 63 7 The Hansard Society.
- BBC Democracy Live Lord McNally
- Full list of new cabinet ministers and other government appointments, guardian.co.uk, 13 May 2010.
- Lib Dems Lord McNally, accessed 3 Nov 2009
- John Hyde, McNally gets legal aid as MoJ portfolios announced Law Gazette, 14 September 2012, accessed 17 September 2011
- Ministerial changes: December 2013, Prime Minister's Office, 18 December 2013.
- Channel Islands APPG,www.parliament.uk, accessed 18 November 2015