The former chief prosecutor for north-west England has urged the Metropolitan police to launch an immediate investigation into Dominic Cummings’ trip from London to Durham at the height of the coronavirus outbreak. Lawyers for Nazir Afzal have written to the Met commissioner, Cressida Dick, arguing that the behaviour of Boris Johnson’s chief adviser during the lockdown warrants a “thorough investigation”. They say the “continuing pressing public imperative to ensure strict compliance” with advice about the pandemic “makes this matter urgent”. Afzal’s lawyers point out that a three-day investigation by Durham police was confined to Cummings’ movement in County Durham and made no finding on why he left London when his wife was suffering coronavirus symptoms and a day before he fell ill with a suspected case. The letter to Dick says: “The apparent wrongdoing included actions in London, including Mr Cummings leaving his home without reasonable excuse on 27 March.” Afzal, whose brother Umar died of coronavirus on 8 April when he was self-isolating at home, has become the figurehead of a legal campaign to ensure that Cummings’ alleged lockdown breaches are fully investigated. As well as writing to Dick, his lawyers, Hodge Jones & Allen, have also written to the chief constable of Durham olice, Jo Farrell, and the director of public prosecutions, Max Hill, calling for further investigation of Cummings’ behaviour. All three letters say the information will enable Afzal, the Crown Prosecution Service and the public “to understand whether Dominic Cummings should be charged and prosecuted for breach of the health protection [coronavirus, restrictions] regulations 2020 and/or related offences”. They point out that a number of public authorities, including the police, have suggested Cummings’ bending of the rules had “undermined the importance of compliance and the made the task of police enforcement with the public more difficult across the country”. The investigation by Durham police found Cummings had probably breached health protection regulations when he took a 52-mile round trip to Barnard Castle with his wife and son on her birthday. The force decided to take no further action and made no finding in relation to the government’s “stay at home” guidance and Cummings’ initial decision to leave London for Durham. The letter to Hill says Durham police’s investigation was “short, narrow and limited” and “did not consider the lawfulness of Mr Cummings leaving London, or other alleged wrongdoing”. It said: “We emphasise on behalf of Mr Afzal that it would be misconceived for the police or the Crown Prosecution Service to approach Mr Cummings’ conduct as if it were insufficiently serious to warrant prosecution at this stage … The seriousness of Mr Cummings’ wrongdoing is an assessment for prosecutors to make, once they have been given the relevant evidence by police and other investigators.” Each of the letters includes a nine-page annex setting out what is known so far about Cummings’ movement during the lockdown alongside the relevant rules at the time. It also includes a list of the “further information required”. Dick, Farrell and Hill have been given 14 days to respond. Afzal is worried that the Cummings affair has damaged public confidence in the law. He said: “I am concerned that the police and prosecutors have not received all the relevant information and their decision making will be incomplete as a result. I am troubled that previous correspondence from people, including MPs, has gone unanswered.” He also encouraged anyone with information about Cummings’ movements during the lockdown to email his solicitor, Mike Schwarz, at mschwarz@hja.net. Schwarz said: “It is Mr Afzal’s simple wish and expectation that current senior police investigators and prosecutors are reminded of their responsibilities and carry out their during in Mr Cummings’ case. By failing to do so they would perpetuate the public’s perception that there is one rule for those in positions of power and another for ordinary citizens.” A spokeswoman for No 10 said it was not commenting on the issue. A CPS spokesman said: “It is not the function of the CPS to investigate allegations of crime. Investigations into alleged criminal conduct are a matter for the relevant police force.” The letters will add pressure on Johnson over the behaviour of his chief adviser. On a LBC phone-in on Friday, Gurvinder from Slough asked the prime minister why he could not see his mother before she died while Cummings could drive 264 miles to stay at his parents’ property at the height of the pandemic. “How do you expect the public to follow the rules if the people setting the rules don’t really care about them themselves?” he asked. Johnson said he “really, really” understood public concern about the issue, and added: “Most people in this country have shown huge forbearance and sacrifice, the overwhelming majority.”