Challen unsuccessfully stood for parliament at the 1992 general election in the constituency of Beverley. He finished in third place and more than 22,000 votes behind the winner James Cran. He entered parliament at the 2001 general election for Morley and Rothwell following the retirement through ill health of Labour MP John Gunnell. Colin Challen was elected with a majority of 12,090 and made his maiden speech on 25 June 2001, in which he spoke of Herbert Henry Asquith who was born in Morley. He was re-elected at the 2005 general election, retaining his seat with a majority of 12,343. A member of the League Against Cruel Sports for almost thirty years, he served on several select committees: The Environmental Audit Committee, the Joint Committee on Consolidation of Bills, the Unopposed Bills Panel and the DECC Select committee. He is an Honorary Associate of the National Secular Society. On 29 January 2007 Challen announced that he would not contest the 2010 general election after a Boundary Commission review abolished his constituency, thus letting Ed Balls contest the new Morley and Outwood constituency, formed from a merger of parts of Morley and Rothwell and Balls' also abolished Normanton constituency. In 2013 Challen opened an art gallery called 'artHERENT' in Scarborough Market, to display recent works. The first exhibition, "Is there any hope for the dead? Reliquaries and other items" started in September 2013. His most recent exhibition "Drawing on Myth" in 2017 was exhibited at the Woodend Creative Workspace in Scarborough. Challen also exhibited in Hull with the Kingston Art Group in 2017 following Hull being named as the City of Culture.
Climate change work
Challen founded the All Party Parliamentary Group on Climate Change in 2005, and has written that he believes the "catastrophic destabilisation of global climate represents the greatest threat that humanity faces." In 2004, Challen presented a Ten Minute Rule Bill introducing the idea of David Fleming's TEQs scheme to Parliament, as a way of guaranteeing that promised emissions reductions would actually be achieved. In 2009, Challen tabled an early day motion calling for all internal UK flights to be phased out before the end of the year, in order to reduce greenhouse gases. He also urged Parliament to cut the national speed limit to 55 mph, and to dedicate two hours of prime-time television each week to explain the dangers posed by climate change. In local elections held in May 2011, Challen was elected as a Labour member of Scarborough Borough Council, representing Castle ward.
Works
The Price of Power: Secret Funding of the Tory Party by Colin Challen, 1998, Vision Paperbacks / Satin Publications,
In Defence of the Party: The Secret State,the Conservative Party and Dirty Tricks by Colin Challen, Mike Hughes 1996, Medium Publishing Co.,
