[6] He stood unsuccessfully as the Conservative Party candidate for the Bristol East constituency in 2001, and for the South West at the European Parliament elections in 2004.

[16] In July 2016, Lopresti was criticised for sponsoring and hosting a parliamentary event at which Bahrain's relationship with the UK was to be celebrated, after the MP had received several thousand pounds' worth of funding for foreign trips to the country.

[17][18] Lopresti was subject to a failed attempt before the 2017 general election by some members of his local party to deselect him as the Conservative Candidate for Filton and Bradley Stoke.

[22] In December 2017, BBC News Online reported that Lopresti was facing an investigation after his ex-office manager made a formal complaint about his behaviour, following her resignation.

A senior Conservative councillor in Bristol subsequently claimed there were "ample grounds" to believe the bullying allegations surrounding the MP due to his "character flaws" and past behaviour.

[23][24] Subsequent to this, the BBC reported on 11 July 2019 that the ex-office manager, Jo Kinsey, felt she had been 'vindicated' following her complaint, having received a letter of apology from Lopresti following an internal Conservative party investigation.

[26][27] Jack was appointed Deputy Chairman of the Conservative Party, serving alongside Nickie Aiken, Lee Anderson, Luke Hall and Matthew Vickers from 2023.

[citation needed] Lopresti lost his seat in parliament in the general election of 4 July 2024, gaining 12,905 votes compared to Labour's Claire Hazelgrove with 22,905.

[28] The Foreign, Commonwealth and Development Office has stated that fighting in Ukraine, or assisting those who are engaged in the war, can lead to prosecution on return to the UK.

[31][32] Following his divorce from Lucy Cope, Lopresti married Andrea Jenkyns MP in St Mary Undercroft in the Palace of Westminster on 22 December 2017 and they have a son named Clifford George, born on 29 March 2017.