[4] His criminal cases have included the Jubilee line corruption trial and successfully defending a member of the Queen's Lancashire Regiment who had been accused of war crimes related to the death of Baha Mousa.

[5] In 2014, Cox successfully defended the former Premier (and current Speaker of the Legislative Assembly) of the Cayman Islands, McKeeva Bush, on charges of corruption and misuse of office.

[6] In March 2015, Cox successfully defended the deputy Editor of The Sun, Geoff Webster, in a trial of four journalists resulting from Operation Elveden.

Burnett announced in 2003 that he would not contest the seat again, and at the 2005 general election Cox defeated the new Liberal Democrat candidate, David Walter, gaining a majority of 3,236.

[16] In February 2016, Cox told the House of Commons that he had concluded, after examining the published renegotiation proposals, that the case for leaving the EU was now overwhelming and that he would vote to do so in the forthcoming referendum.

[21] On 9 July 2018, Theresa May appointed Cox as attorney general taking over from Jeremy Wright following a Cabinet reshuffle, prompted by the resignations of David Davis and Boris Johnson.

[22] On 1 December 2018, The Sunday Times newspaper reported the leaked contents of a recent letter written by Cox to Cabinet Ministers detailing the Attorney General's legal advice on Theresa May's Brexit deal.

[25] The next day Cox appeared in the House of Commons to answer an urgent question on the Government's legal advice and on the implications of the Supreme Court's decision.

[26] In February 2020, Cox said the public is concerned about the creeping "judicialisation of politics" and said people were right to worry that unelected officials were making decisions that ought to be taken by Parliament.

"[27][28] On 13 February 2020, in a Cabinet reshuffle, Cox was dismissed as attorney general, at the request of the prime minister, Boris Johnson, and replaced by Suella Braverman.

Cox registered the payments late, between two and seven months after the deadline; he said that he had omitted to prioritise the rule in the midst of an intense political and professional schedule.

[33] On 9 July 2018, Cox gave up all private practice upon his appointment as attorney general,[34] but resumed sometime after being sacked in February 2020, working as "consultant global counsel" to the international law firm Withers LLP.

[35] He earned "£468,000 a year for 48 hours of work per month"[35] including over £150,000 for advising the government of the British Virgin Islands about alleged corruption in a case bought by the Foreign Office.

[36] Beginning on 26 April 2021, Cox spent one month in the Caribbean and with the permission of the chief whip, continued to vote in Parliament via proxy due to the coronavirus lockdown.

[37] On 10 December 2019, Danish media claimed that Cox had earned £380,000 (3.4 million DKK)[38] in legal fees during the years 2015–2017 for representing Sanjay Shah, a Dubai-based British businessman and prime suspect in what is reported to have been the largest tax fraud case Denmark had ever seen.