List of British political defections

This is a list of notable defections or splits made by United Kingdom parliamentarians. They must have either been sitting MPs, MSPs or MEPs at the time, or in between sessions.

Year Name Original affiliation New affiliation Notes
1888 Robert Cunninghame-Graham Liberal Scottish Labour The first socialist MP.
1904 Winston Churchill Conservative Liberal
1919 Cecil L'Estrange Malone Liberal British Socialist Party subsequently joined the Communist Party of Great Britain.
1920 Oswald Mosley Conservative Independent
1924 Oswald Mosley Independent Labour
1924 Winston Churchill Independent (Constitutionalist) Conservative
1931 Oswald Mosley Labour New Party
1931 Ramsay MacDonald and
Philip Snowden		 Labour National Labour
1946 Ernest Millington Common Wealth Labour
1947 Campbell Stephen,
John McGovern and
James Carmichael		 Ind. Labour Party Labour
1948 Tom Horabin Liberal Labour
1948 Ivor Thomas Labour Conservative
1949 Alfred Edwards Labour Conservative
1955 Richard Acland Labour Independent
1962 Alan Grahame Brown Labour Conservative
1968 Desmond Donnelly Labour Independent Later formed the Democratic Party
1974 Christopher Mayhew Labour Liberal
1976 John Stonehouse Labour English National Party
1976 Jim Sillars Labour Scottish Labour
1976 John Robertson Labour Scottish Labour
1977 Reginald Prentice Labour Conservative
1981 Tom Bradley,
Ronald Brown,
John Cartwright,
Richard Crawshaw,
George Cunningham,
Bruce Douglas-Mann,
James Dunn,
Tom Ellis,
David Ginsburg,
John Grant,,
John Horam
Ednyfed Hudson Davies,
Edward Lyons,
Dickson Mabon,
Robert Maclennan,
Tom McNally,
Bryan Magee,
Edmund Marshall,
Bob Mitchell,
Eric Ogden,
Michael O'Halloran,
David Owen,
William Rogers,
Neville Sandelson,
Jeffrey Thomas,
Michael Thomas,
Ian Wrigglesworth and
James Wellbeloved		 Labour Social Democrat In addition to Owen and Rogers, the "Gang of Four" who originally founded the SDP included Shirley Williams and Roy Jenkins neither of whom were MPs at the time of their defections.
1981 Christopher Brocklebank-Fowler Conservative Social Democrat
1983 Michael O'Halloran Social Democrat Independent Labour
1984 Michael Gallagher MEP Labour Social Democrat
1990 Dick Douglas Labour SNP
1995 Alan Howarth Conservative Labour
1995 Emma Nicholson Conservative Liberal Democrat
1996 Peter Thurnham Conservative Liberal Democrat
1997 George Gardiner Conservative Referendum Party
1997 Peter Temple-Morris Conservative Labour Sat as a "One Nation Conservative" until 1998
1999 Shaun Woodward Conservative Labour
2000 Bill Newton Dunn MEP Conservative Liberal Democrat
2001 Paul Marsden Labour Liberal Democrat
2002 Richard Balfe MEP Labour Conservative
2002 Andrew Hunter Conservative Democratic Unionist Did not take party whip until 2004
2003 Margo MacDonald SNP Independent
2004 Jeffrey Donaldson Ulster Unionist Democratic Unionist
2004 George Galloway Labour Respect Independent until formation of RESPECT.
2004 Campbell Martin SNP Independent
2004 Robert Kilroy-Silk MEP UKIP Veritas
2005 Robert V. Jackson Conservative Labour
2005 Brian Monteith MSP Conservative Independent
2006 Clare Short Labour Independent
2007 Quentin Davies Conservative Labour
2007 Sajjad Karim MEP Liberal Democrat Conservative
2008 Bob Spink Conservative UKIP redesignated as an Independent, on the grounds that UKIP had no 'whip'
2010 Edward McMillan-Scott MEP Conservative Liberal Democrat Expelled from the Conservative Party in September 2009 having successfully stood for re-election as Vice-President of the European Parliament against the candidate endorsed by the grouping including the Conservative Party in July 2009.
2010 Sylvia Hermon Ulster Unionist Independent

See also