He was subsequently Chairman of the Conservative Party and Shadow Secretary of State for the Office of the Deputy Prime Minister under Iain Duncan Smith.
On 12 June 2008 Davis unexpectedly announced his intention to resign as an MP and was immediately replaced as Shadow Home Secretary; this was in order to force a by-election in his seat, for which he intended to seek reelection by mounting a specific campaign designed to provoke wider public debate about the erosion of civil liberties in the United Kingdom.
Later, after his half-sister was born, the family moved to a council estate in Tooting, his stepfather being a shop steward at Battersea Power Station.
He subsequently worked as an insurance clerk and became a soldier in the Territorial Army's 21 SAS (Artists) to earn the money needed to retake his examinations.
[4] Davis worked for Tate & Lyle for 17 years, rising to become a senior executive, including restructuring its troubled Canadian subsidiary, Redpath Sugar.
[9] In 1999, Davis presented the Parliamentary Control of the Executive Bill to the House of Commons, in which he proposed to transfer ministerial exercise of the Royal Prerogative to the Commons in the following areas: the signing of treaties; the diplomatic recognition of foreign governments; European Union legislation; the appointment of ministers, peers and ambassadors; the establishment of Royal Commissions; the proclamation of Orders in Council unless subject to resolutions of the Commons; the exercise of the powers of the executive not made by statute; the declarations of states of emergency; the dissolution of parliament.
[12] Davis used his first interview as Shadow Home Secretary in November 2003 to state his personal support for a reintroduction of the death penalty for people convicted of multiple murder "where there is clear evidence and no doubt" surrounding the offender's guilt, citing the Yorkshire Ripper Peter Sutcliffe and Moors Murderer Ian Brady as examples of offenders who would fall into that category.
Davis was initially the front runner in the contest, but after a poorly received speech at that year's Conservative Party Conference his campaign was seen to lose momentum.
Despite a strong performance in a BBC Question Time head-to-head debate in the final stage of the leadership contest, Davis could not match his rival's general popularity.
As Shadow Home Secretary, Davis turned the Conservatives away from the Labour Party's plan to reintroduce identity cards, citing spiralling costs and libertarian issues.
[23][24] Galley initially approached Davis stating he had access to government immigration details which he was willing to leak to help the Conservative Party.
[25] In April 2009, following a disciplinary hearing, Galley was dismissed from his job as a junior Home Office official for leaking information to Green.
[32] He also spoke at the 2009 Guardian Hay Festival, where he criticised Labour's "illusory pursuit of an unobtainable security", and was well received by an overwhelmingly non-Conservative audience.
[34] Davis supported civil liberties campaign group Big Brother Watch and in January 2010 he spoke with Tony Benn at the official launch.
[35] In 2012 he helped lead the opposition to Coalition plans to allow police and security services to extend their monitoring of the public's email and social media communications.
[37] In 2014, along with Labour MP Tom Watson, he challenged the government's introduction of the Data Retention and Investigatory Powers Act 2014 in the courts.
[42] Davis has taken more conservative stances on some other civil liberties issues, having repeatedly voted to restrict abortion, fertility treatment and embryo research.
"[46] Davis was amongst the signatories of a letter in 2012 to The Guardian condemning the Coalition's efforts to hide the UK's involvement in rendition and torture behind secret trials.
[50][51] In May 2010, with the result of a hung parliament, it was reported that David Cameron wanted to invite Davis and other right-wingers such as Michael Howard and Iain Duncan Smith into his Conservative–Liberal Democrat coalition cabinet.
[76] Some politicians were angry because reports about the potential effect of Brexit on 58 economic sectors were severely edited before Davis gave them to the Exiting the European Union Select Committee.
They maintained Davis – and by implication Theresa May's government – chose to disregard a binding and unanimous vote from MPs requiring the information to be provided in full.
[77] Davis later appeared to contradict his earlier assurances that impact analyses had been carried out when he said the government had not produced any economic forecasts of what would happen after the UK leaves the EU.
[91] On 17 March 2021, Davis used parliamentary privilege to criticise the Scottish Government's investigation into allegations of sexual misconduct by former First Minister Alex Salmond.
Davis, a close personal friend of Salmond, told MPs during a Commons debate that there had been a "concerted effort" by SNP officials to encourage complainers to come forward, and that Nicola Sturgeon's chief of staff, Liz Lloyd, had been involved in the civil service investigation into Salmond in February 2018 – months before Nicola Sturgeon claimed to have known about the investigation.
He told the House of Commons, "I have it on good authority that there exists from 6th Feb 2018 an exchange of messages between civil servants suggesting that the first minister's chief of staff is interfering in the complaints process against Alex Salmond.
He quoted what Leo Amery (alluding to Oliver Cromwell) had said to Prime Minister Neville Chamberlain in 1940: "You have sat there too long for all the good you have done.
"[95][96] On 2 October 2022, Davis wrote an article in The Daily Telegraph which advocated for reform of the National Health Service and the adoption of a social insurance-based system.
[100][101] On 18 July 2024, Davis again used parliamentary privilege to name Liz Lloyd, Nicola Sturgeon's ex-chief of staff, as the person responsible for leaking sexual misconduct allegations against Alex Salmond to the Daily Record in 2018.