Mark Oaten (born 8 March 1964, Watford) is a Liberal Democrat politician in the United Kingdom, and Member of Parliament for the Winchester constituency. Oaten served as the Liberal Democrat Shadow Home Secretary (the party's main Home Affairs spokesman), before resigning that position on 21 January 2006 after a sex scandal involving male prostitutes and coprophilia was uncovered by the News of the World tabloid newspaper. Oaten has confirmed he will not be standing for re-election at the next general election.