A member of the Liberal Democrats, he gained the seat from Rebecca Pow of the Conservative Party with a majority of 11,989 in the 2024 United Kingdom General Election.

[7] Amos sat on advisory groups for planning and eco-development at the Department for Communities and Local Government.

[11] In the 2009 New Year Honours, Amos was appointed Officer of the Order of the British Empire (OBE) for services to sustainable development.

[12] Amos was a Liberal Democrat member of Oxford City Council for the ward of Central from 1992 to 1996, serving on a planning committee.

[14] He defeated Pow in the new constituency of Taunton and Wellington at the 2024 general election, achieving 48.4 per cent of the vote and a majority of 11,939.