He moved to East Sussex in 2006 and was elected to
Wealden District Council for the
Rotherfield ward in 2007 and was re-elected in 2011. Merriman stood as a Conservative candidate for
North East Derbyshire in the
2010 general election. He came second to the incumbent Labour MP
Natascha Engel. Merriman was selected as the
prospective parliamentary candidate (PPC) for
Bexhill and Battle in November 2014. Other contenders for the seat included future MPs
Suella Fernandes (now Braverman) and
James Cleverly. He won the seat in the
2015 general election with 30,245 votes and a majority of 20,075 (36.4%). During the 2015–2017 parliament, he sat on the
Procedure Committee. From July 2017 to August 2018, he was a
parliamentary private secretary (PPS) in the
Department for Work and Pensions. Merriman was appointed as PPS to then
Chancellor of the Exchequer Philip Hammond. He supported the UK remaining within the
European Union (EU) in the
2016 UK EU membership referendum. Merriman voted for then Prime Minister
Theresa May's
Brexit withdrawal agreement in early 2019. In the indicative votes held on 27 March, he voted for a
referendum on the Brexit withdrawal agreement. Merriman supported
Jeremy Hunt in the
2019 Conservative leadership election. He voted for Prime Minister
Boris Johnson's Brexit withdrawal agreement in October 2019. Merriman was the chair of the
Transport Select Committee between January 2020 and October 2022. He had previously been a member of the committee since September 2017 and was also a member of the
Liaison Committee between May 2020 and October 2022. Merriman was appointed as
Minister of State for Rail and HS2 in October 2022. Merriman did not stand for re-election at the
2024 general election. ==Post-parliamentary career==