- Eric Joyce, the Labour Member of Parliament for Falkirk, is arrested after an alleged brawl in a House of Commons of the United Kingdom bar.
- The British House of Commons votes to reject a proposed referendum on Britain's membership of the European Union, with 483 MPs voting against the proposal and 111 voting in favour. Among those who supported the proposal were 81 Conservative Party members, who rebelled against the anti-referendum stance of Prime Minister David Cameron, the leader of the Conservative Party.
- Twenty members of the United Kingdom's Parliament demand House of Commons Speaker Michael Martin's resignation, amid at the 2009 expenses scandal. [http:--news.bbc.co.uk-1-hi-uk_politics-8054657.stm (BBC)] [https:--www.telegraph.co.uk-news-newstopics-mps-expenses-5344495-Speaker-Michael-Martin-sorry-but-refuses-to-resign.html "(The Daily Telegraph)"]
- British Member of Parliament John McDonnell (Hayes and Harlington) is suspended after manhandling the ceremonial mace during House of Commons proceedings.
- Speaker of the House of Commons of the United Kingdom Michael Martin accuses Scotland Yard of not having a search warrant before its officers entered Member of Parliament Damian Green's Commons office and failing to inform Serjeant-at-Arms Jill Pay that she was entitled to request one.