Hospital bosses who failed to act on concerns about the killer nurse Lucy Letby should be investigated by police for corporate manslaughter, says the prosecution’s key medical expert. Speaking to the Observer, Dr Dewi Evans, whose evidence was central to the case against Letby, said executives were “grossly negligent” for not acting on fears about the nurse as she murdered seven babies and attempted to kill another six. The Observer can also reveal that managers blamed other NHS services for many of the unexplained deaths and declared in a two-page review in May 2016 that there was “no evidence whatsoever against [Letby] other than coincidence”. By that time, senior doctors had been raising the alarm for months after the nurse had murdered five newborns and attempted to kill another five. She went on to kill two triplet brothers and tried to kill an eighth baby the month after this document was produced. Letby, who was in her mid-20s when she carried out the attacks, is expected to become only the third woman alive to be handed a whole-life term, meaning she will never be released from prison, when she is sentenced on Monday. She was found guilty of murdering seven babies and attempting to kill another six at the Countess of Chester hospital in north-west England, making her the worst child serial killer in modern Britain. The nurse, now 33, was cleared of two counts of attempted murder, and jurors were unable to reach verdicts on a further six charges after a 10-month trial at Manchester crown court. Senior doctors first reported Letby’s link to unusual deaths and collapses to executives on 2 July 2015, after three babies died and another suffered a near-fatal deterioration in just two weeks the previous month. Several consultant paediatricians raised the alarm on a number of occasions over the following year as the number of suspicious incidents grew and Letby was found to be present at all of them. However, executives failed to launch a formal investigation until July 2016, more than a year after Letby’s link had first been raised. She was removed from the unit that month, but the police were not contacted until May 2017. Evans, a consultant paediatrician who gave evidence in court about each of Letby’s 13 victims, said that three murders could have been prevented if hospital bosses had acted more urgently on concerns. He said more should have been done when Letby’s first three victims died within 14 days in June 2015 and again when twins were attacked in August, one fatally and the other injected with insulin. Evans, 74, a National Crime Agency-accredited expert who has given medical evidence in hundreds of cases since 1988, said he would ask Cheshire constabulary to investigate the hospital management’s “grossly irresponsible” failure to act. He said: “They were grossly negligent. I shall write to Cheshire police and ask them, from what I have heard following the end of the trial, that I believe that we should now investigate a number of managerial people in relation to issues of corporate manslaughter. “I think this is a matter that demands an investigation into corporate manslaughter. The police should also investigate the [hospital] in relation to criminal negligence.” He added: “Failing to act was grossly irresponsible – let’s make it as clear as that. We are talking about a serious emergency. It’s grossly irresponsible and, quite frankly, unbelievable [that they failed to act sooner].” Evans called for the police investigation after being told about a review produced by the manager of the unit where Letby worked in May 2016 that stated: “There is no evidence whatsoever against LL [Lucy Letby] other than coincidence.” By this point, senior doctors had been asking for “urgent” meetings with executives for months to discuss their concerns after five murders and the attempted murder of another five babies. But nothing appears to have happened until this two-page document was produced in May 2016, effectively clearing Letby of any wrongdoing and blaming other NHS services for the deaths. Letby went on to murder two newborn triplet brothers and attempt to kill a sixth child the following month. The review, which is being made public for the first time, states: “LL works full time and has the qualification in speciality. She is therefore more likely to be looking after the sickest infant on the unit. LL also avails herself to work overtime when the acuity or unit is over capacity. “There are no performance management issues, and there are no members of staff that have complained to me or others regarding her performance. I have found LL to be diligent and have excellent standards within the clinical area.” It goes on to state that there had been a higher death rate on the unit in the year to May 2016 but blamed other NHS services for a number of the mortalities: “The Cheshire and Mersey transport service have been involved in a few of these mortalities and they may have survived if the service was running adequately. “Alder Hey children’s hospital’s failure in facilitating a cot also added to the complexities of these mortalities. If there had been a bed sooner the infant may not have died.” Several of the executives involved, who have now left the Countess of Chester hospital, said they would cooperate fully with the independent inquiry announced by the health secretary, Steve Barclay, on Friday. The Countess of Cheshire hospital NHS foundation trust has declined to answer questions about its handling of the case but its executive medical director, Dr Nigel Scawn, said in a statement on Friday: “I speak for the whole Trust when I say how deeply saddened and appalled we are at Lucy Letby’s crimes. “We are extremely sorry that these crimes were committed at our hospital and our thoughts continue to be with all the families and loved ones of the babies who came to harm or died. We cannot begin to understand what they have been through.”