The attorney general, Suella Braverman, is facing calls to resign after she joined the chorus of Downing Street loyalists defending Dominic Cummings’s trip to Durham during lockdown. Lawyers expressed astonishment that Braverman should have joined in what opponents described as an “orchestrated political” action. Her intervention, it is alleged, undermines the independence of her office as the government’s chief legal adviser and puts her in an impossible position in relation to any subsequent police inquiry. The calls follow Braverman’s tweet on Saturday in which she quoted the full text of the No 10 statement on Boris Johnson’s chief aide in which the prime minister said he had behaved “responsibly and legally”. She added: Braverman was one of small number of senior cabinet members, all close political allies of Boris Johnson, who retweeted the statement. Philippe Sands QC, a professor of international law at University College London, said: “The absolute integrity of an attorney general is the prerequisite for a functioning democracy. When doubt is cast over the integrity of an attorney general, that person has to go. “She must have known that the possibility could not be excluded that the Durham police would have been involved. She has completely extinguished with a single tweet her integrity.” “She’s the adviser to the prime minister on matters of law and she therefore needs to be absolutely scrupulous to maintain an independent position on legal matters. “The prime minister has expressed a view on on the legality and propriety of what Cummings has done. In expressing that view, did he seek advice from the AG? “There’s a conflict between her position constitutionally providing independent advice to the prime minister and her role as an MP tweeting political support. She can do one or the other; she can’t do both.” Sir Geoffrey Nice QC, a former judge and war crimes prosecutor, said: “Any experienced courtroom lawyer knows that there are lines of inquiry and documentary records that would prove or disprove the allegations in minutes or hours. Every lawyer knows that records can prove what individuals, with interest to serve, may obscure by lies. Ms Braverman was unwise to back words over undisclosed records. “The uncertainty and anger generated will allow others, as a minimum, to be ‘generous’ with their own understanding of the rules. That may increase the spread and lead to further avoidable deaths.” The shadow attorney general, Lord Falconer QC, wrote to Braverman on Sunday accusing her of undermining the legal independence of her office and the law. In his letter, he said: “Your tweet appears to side with Mr Cummings in the dispute with the police. It implies you are not supportive of the steps they took. “Moreover, your tweet is supportive of a statement from No 10 which disputes the handling of the case by the police. The prime minister should not be lending his authority to attacks on the enforcement of the criminal law. He should certainly not be egged on in that by the attorney general. “As attorney general you have a special constitutional responsibility for the appropriate enforcement of the criminal law and are responsible for oversight of criminal prosecutions. “It is a rigid constitutional principle that the attorney general will discharge those functions free from political considerations or influence. It looks clear that your tweet was part of politically orchestrated campaign in support of Mr Cummings and you have breached that rigid principle.” The Scottish National party spokesperson in the Commons on justice, Joanna Cherry QC, also expressed her outrage, tweeting: Braverman’s two immediate predecessors as attorney general, Geoffrey Cox QC and Dominic Grieve QC, are widely regarded to have been removed from office because they put their office’s legal independence above party politics. In a separate post, the barrister Kirsty Brimelow QC, who has highlighted legal problems with coronavirus prosecutions, argued that there were questions over whether Cummings’ behaviour had been legal. She wrote: “There are questions to be answered as to how Mr Cummings says that he acted legally. Indeed, unlike all those people who have been prosecuted to date, Mr Cummings’ household actually did have Covid-19. “As to the responsibility of his actions, it is completely clear that Mr Cummings breached government guidance which is presumed to be responsible.” The attorney general’s office declined to comment about Braverman’s tweet.