Colvile says his interest in politics took hold whilst at Stowe School when he became fascinated by how an idea could become law or a policy to protect civil liberties, to enhance people's freedom and for the enjoyment of life.

[5] Colvile unsuccessfully contested the Plymouth Sutton constituency in the 2001 and 2005 general elections, both times losing to the sitting Labour MP Linda Gilroy.

Colvile won its successor seat, Plymouth Sutton and Devonport, at the 2010 general election with a majority of 1149 and 34.3% of the votes cast, ousting Gilroy with a swing of 6.9% calculated after allowing for significant boundary changes.

[9] Colvile was criticised when it was revealed in October 2011 that he received hospitality equivalent to £694.80 from Japan Tobacco, owners of the Benson & Hedges and Silk Cut brands, paying for a visit to see Test match cricket at The Oval that summer, coming shortly after he voted in favour of relaxing the smoking ban.

[10] Colvile was again criticised in July 2013 when it was revealed he received two free tickets (worth £1,260) to the RHS Chelsea Flower Show, again from Japan Tobacco.