[8][9] He made his maiden speech on 12 July, where he set out his vision for what he wanted to achieve whilst an MP, during the debate on Corporation Tax.
[15] He was made Parliamentary Under-Secretary of State at the Department for Transport on 8 July 2022 as part of the caretaker administration of outgoing Prime Minister Boris Johnson.
[18] From January to June 2020, McCartney claimed £21,600 in expenses for Anagallis Communications, a firm run by a donor who helped fund his first election campaign.
In consequence, more than 20 sitting Conservative MPs,[23] including McCartney, were investigated by Lincolnshire Police over whether he breached election spending rules.
[26] In advance of the 2017 general election, McCartney issued a letter to all other candidates for the Lincoln seat, warning of legal action against false, misleading or defamatory statements in the wake of investigations into the party's spending.
[27] In January 2021, the JCIO issued a formal warning to McCartney for referring to his role as a Magistrate in election material, despite having been reprimanded for this previously.
In reaching their decision, the JCIO noted that McCartney had previously received a disciplinary sanction for similar behaviour and was unwilling to acknowledge the inappropriateness of his actions.
[28] In response, McCartney publicly stated that the complaint was "politically motivated", that he had not been previously reprimanded and that he complied with relevant guidance.
[29] In July 2021, it was announced that the Parliamentary Commissioner for Standards was investigating McCartney for failing to declare an interest in a company run by his brother.
[33] During the referendum campaign, McCartney led the Greater Lincolnshire Vote Leave Grand Tour on 14 June 2016 which included visiting 14 towns across the county in one day.
Following an interim report on the connections between colonialism and properties now in the care of the National Trust, including links with historic slavery, McCartney was among the signatories of a letter to The Telegraph from the "Common Sense Group" of Conservative Parliamentarians in November 2020.
[39][40][41] In April 2012, McCartney said that publication of the results of the Department for Education's investigation into allegations of misuse of funds at Lincoln's Priory Federation of Academies Trust should be delayed until the decision was made by the then Secretary of State.
[58] After a hostile response, the councillor, a Conservative chairman in Margaret Thatcher's home town of Grantham deleted the remark and apologised.
After criticism from Labour candidate Lucy Rigby, who noted that only 1 in 5 Conservative MPs were women, McCartney replied that those with a sense of humour would appreciate the remark, though he said the comment was addressed to another Twitter user joining the debate.
[59] He made it onto a six-man shortlist for the position,[60] but missed out on the nomination which went to Rob Waltham following a selection event at Lincoln's Bishop Grosseteste University in December 2024.
He lists his recreations as "myriad of sports—football, Rugby, cricket, croquet, snowboarding, shooting; classic cars, green laning, trains, gardens, architecture, history, dance music, relaxing with family and friends, cooking".