Baillie was a councillor in the
London Borough of Camden from 2014 to 2018, representing the ward of
Frognal and Fitzjohns. As an opposition member she served on the Children, Schools and Families Scrutiny Committee and during the 2016–2017 civic year she chaired a review of mental health service provision for young people. She stood for the
Bermondsey and Old Southwark seat at the
2017 general election. She was third behind the
Labour and
Liberal Democrat candidates with 13% of the vote. She had previously unsuccessfully sought selection for the
Hampstead and Kilburn constituency for the same election, and for the
Barnet and Camden London Assembly seat at the
2016 election. Baillie was selected as the Conservative candidate for
Stroud on 31 July 2018. She supported the UK remaining within the EU in the
2016 UK EU membership referendum, but during her 2019 election campaign indicated that she now supported
Brexit, to honour the result of the referendum. At the
2019 general election, she was elected as an MP with a majority of 3,840 (5.8%). The seat had been represented by
Labour and Co-operative MP
David Drew since the 2017 election. Baillie was the first woman to represent the constituency. She was appointed to the
Work and Pensions Select Committee in March 2020. In July 2021, Baillie commented that she opposed the removal of the
Blackboy Clock in Stroud as she felt that it was important to leave all statues to "reflect our country's journey in the 20th and 21st centuries toward equality" but supported adding "factual information" on the "origins of its imagery". Baillie endorsed
Rishi Sunak in the
July–September 2022 Conservative Party leadership election and the subsequent
October 2022 Conservative Party leadership election. She apologised in August 2023 for wrongfully claiming that she had created the Natural History GCSE on her website and in a campaign leaflet. Baillie lost her seat in the
2024 general election to Labour's
Simon Opher. ==Personal life==