Allan was elected as a local councillor to Wandsworth London Borough Council in 2006, representing the Southfields ward, and served until 2012. In March 2013 she was selected as the Conservative Party parliamentary candidate to contest the marginal constituency of Telford in the 2015 general election. She advocated a direct rail link to London from the town and aimed to tackle the high rate of youth unemployment in Telford.
Family First Campaign
After Allan made a visit to her GP seeking help with symptoms of depression following a family bereavement in 2010, Wandsworth Council launched a child protection investigation, claiming Allan's 10-year-old son was at risk of significant harm. In the wake of the controversy which followed, Allan stood down from the Council, and from her directorship with the NHS. In 2011, following legal action by Allan, social services decided to take no further action. Based on her family's experience, she founded Family First Group, a lobby group which campaigns to reduce the number of children in state care, for improvements to the UK child protection system and support for families affected by it. In 2012 Allan fronted a media campaign on child protection injustice, which included an appearance on ITV's This Morning. She used the media coverage to build a political profile for the Family First Campaign, working with Ministers, children's charities, and families to identify and remedy shortcomings in the child protection system. She participated in an edition of ITV's Exposure documentary series on this subject on 15 July 2014, Don't Take My Child.
Death threat controversy
In December 2015 Allan posted on Facebook an email she said she received from a constituent; the email was edited and ended with the words "unless you die". Allan later acknowledged that she had added those words to the email – leading to accusations of her faking a death threat. Allan temporarily deactivated her Facebook and Twitter accounts following the incident. Allan later apologised for creating a "misleading impression", and said the controversy was not about her use of social media, but due to "activists unhappy they didn't get the MP they wanted".
Allegations of bullying staff
In December 2015 Allan was accused of bullying members of staff, and leaving a series of voicemail messages to a sick employee allegedly including a threat of dismissal. On 21 December 2015, a statement about the allegations was published on Allan's website but deleted later in the day. The statement apologised for Allan's voicemail messages, which were publicly released, but stated the bullying allegations were unfounded and was critical of a former employee; the London Evening Standard characterised the statement as "a long rebuttal". Later in January 2016, Allan acknowledged sending the voicemails was "stupid" and she regretted shouting at the employee, but denied her actions amounted to bullying.
NHS junior doctors strike
In April 2016 Allan used Facebook to say: "Hard-working people in Telford don't get why privileged trainee doctors, on course to earn £100,000 plus, will hold NHS to ransom and deprive ordinary people of emergency care. I don't get it either." Her comments were criticised by junior doctors, with one saying that many of her fellow graduates were still junior doctors who can work “horrific shift patterns” and move hospital every 12 months.
Advancing "libertarian agenda"
In January 2016 Allan stated that on national issues her approach in general is to advance within parliament the "libertarian agenda", to prevent the increasing influence of the state. For example, she was against a sugar tax that was under consideration by her party. Allan voted to leave the EU in the June 2016 referendum. In June 2016 Allan introduced a private member's bill to repeal provisions in the Counter-Terrorism and Security Act 2015 to require staff to report possible signs of extremism or radicalisation amongst primary and nursery school aged children, following a number of high-profile cases where the provision was inappropriately used in relation the government's Prevent strategy.
European Union
Allen is a supporter of Brexit, and has argued that the country must be prepared to walk away with a no-deal if necessary. In April 2019, Allan welcomed whom she called the "fantastic" candidates from the Brexit Party ahead of that year's European elections. She defended the comment after being criticised by Tory loyalists, saying that party loyalties would be "eclipsed" by the Brexit issue at the ballot box.
Retweet of doctored Keir Starmer video
On 14 May 2020, Allan was criticised after she retweeted a doctored video from a far-right Twitter account which falsely claimed that Labour leaderSir Keir Starmer obstructed the prosecution of grooming gangs while he served as Director of Public Prosecutions. Allan was reprimanded for her actions by Conservative whips, but has yet to apologise.
Personal life
Allan is married to a stockbroker and has a son. They live in Southfields, Wandsworth. Allan also has a constituency house in Lawley Bank, Telford.