At the
2015 general election, Double was elected to Parliament as MP for
St Austell and Newquay with 40.2% of the vote and a majority of 8,173. Double previously chaired the now defunct All Party Parliamentary Group Ocean Conservation, working with Cornish charity
Surfers Against Sewage. The group had campaigned against marine litter and sought to protect the coastline. Double supported
Brexit in the
2016 EU membership referendum. Double has helped secure Government backing for a new link road between the A30 and St Austell. Double was vice-chair of the Parliamentary Beer Group which works to support pubs and breweries. In this role, he had been able to promote the work of
St Austell Brewery, who operate from his constituency. He was also a member of the now defunct Ceramics All Party Parliamentary Group which represented the ceramics industry, including
China Clay. He also sat on the Parliamentary Space Committee where he promoted Newquay as a frontrunner for the location of the UK's first spaceport. At the snap
2017 general election, Double was re-elected as MP for St Austell and Newquay with an increased vote share of 49.5% and an increased majority of 11,142. Double has served in Parliament as a Member of the
Petitions Committee, the European Scrutiny Committee and the Transport Committee. In December 2018, during the
no-confidence vote against
Theresa May as leader of the party, Double said he would vote against the then-Prime Minister. In August 2019, Double was appointed
Parliamentary Private Secretary to the
Department of Health and Social Care. At the
2019 general election, Double was again re-elected with an increased vote share of 56.1% and an increased majority of 16,526. On 17 September 2021, Double was appointed an
Assistant Government Whip in the second
cabinet reshuffle of the
second Johnson ministry. In July 2022, he was appointed
Parliamentary Under-Secretary of State at the
Department for Environment, Food and Rural Affairs. He was sacked in September 2022 by new Prime Minister
Liz Truss. He joined a number of colleagues in calling for Truss's resignation, after confusion over a vote on
fracking. On 28 October 2022, Double was appointed
Lord Commissioner of the Treasury (Government Whip) covering the Ministry of Defence by new Prime Minister Rishi Sunak, ==Personal life==