Lucy Letby

Lucy Letby (born 4 January 1990) is a British former neonatal nurse who murdered seven infants and attempted the murder of seven others between June 2015 and June 2016. Letby attracted suspicion following a high number of infant deaths which occurred at the neonatal unit of the Countess of Chester Hospital shortly after she began working with children in the hospital's intensive care unit.

Letby was charged in November 2020 with eight counts of murder and ten counts of attempted murder. Letby pleaded not guilty, and told a subsequent Nursing and Midwifery Council disciplinary panel that she is innocent. Her methods, revealed during the course of her ten-month trial from October 2022 and August 2023, included injecting the infants with air or insulin, overfeeding them, and physically abusing them with medical tools. Letby accepted at trial that test results showed some victims had been injected with insulin, but blamed others. She also removed over 250 confidential nursing handover sheets from her workplace, and falsified patient records to avert suspicion.

On 21 August 2023, Letby was sentenced to life imprisonment with a whole life order. In July 2024 she was further convicted of attempting to murder another child at the hospital, after the jury at her original trial failed to reach a verdict on the charge. An application to appeal her conviction was refused by the Court of Appeal in April 2024.

Letby is the most prolific serial child killer in modern British history; the Cheshire Constabulary now suspects that she may have claimed more victims, including at Liverpool Women's Hospital, where two infants died during her training. Management at the Countess of Chester Hospital were criticised for ignoring warnings about Letby that could have prevented some of the killings. The British government has commissioned an independent statutory inquiry into the circumstances surrounding the murders.

Early life and education
Lucy Letby was born on 4 January 1990 in Hereford, Herefordshire, the only child of a finance manager and an accounts clerk. She was educated at Aylestone School and Hereford Sixth Form College. She had had a very difficult birth herself and was, according to a friend who knew her since secondary school, "very grateful for being alive to the nurses who would have helped save her life". This, the friend states, had led her to want to be a nurse all her life. Letby pursued her education in nursing at the University of Chester, where she also worked as a student nurse during her three years of training, carrying out placements at Liverpool Women's Hospital and the Countess of Chester Hospital. Letby was the first member of her family to study at university and graduated in September 2011.

Career
Letby began working as a registered nurse at the neonatal unit of the Countess of Chester Hospital in 2012. In a 2013 staff profile, she said that she was responsible for "caring for a wide range of babies requiring various levels of support" and that she enjoyed "seeing them progress and supporting their families." Letby also took part in a campaign to raise funds for a new neonatal unit at the hospital. Letby told others that she found non-intensive care work "boring".

Letby had two training placements at Liverpool Women's Hospital, in late 2012 and early 2015, which came under investigation after her conviction. In 2015, Letby qualified to work with infants in intensive care, and in April 2016, she was reassigned by the ward manager from night shifts to day shifts.

In June 2016, consultants asked management to remove Letby from clinical duties pending an investigation into her conduct. Letby was transferred to the patient experience team in July 2016 and later to the risk and patient safety office, working there until her arrest in 2018.

Initial investigations
In June 2015, four collapses occurred in the same neonatology unit of Countess of Chester Hospital, three leading to infant deaths. The unit typically saw only two or three deaths a year, and the infants involved had failed to respond normally to resuscitation attempts. A consultant and lead neonatologist conducted an informal review, and reported the incidents to the committee of the NHS Foundation Trust responsible for addressing serious incidents. Upon review, the committee classed the deaths as medication errors. Stephen Brearey, the unit's head, observed that Letby had been on shift for all of the incidents, but considered it an unsurprising coincidence; there was only one other qualified junior nurse in the unit, and Letby often worked extra shifts to cover for staffing shortages. Later, medical consultants for the Cheshire Constabulary told police that it was unusual for infant collapses to be unexpected and unexplained, as these were. In fact, studies have found that about half of unexpected infant collapses remain unexplained after an autopsy.

In October 2015, a ward manager conducted her own review, noting that Letby was the only staff member consistently present throughout these incidents of unexplained collapses and deaths. These findings were relayed to the lead neonatologist. Further concerns were voiced to management by the unit's consultants that same month; concerns were either resisted by the Trust Executives or ignored. In February 2016, the lead neonatologist, along with other consultants, concluded a thematic review investigating five unexplained deaths and collapses within the unit. Their investigation determined that the only common factor in these cases was the presence of Letby. The lead neonatologist contacted the unit manager, the hospital's medical director and the director of nursing, requesting an urgent meeting. A meeting took place in May 2016. The executive team deemed the spike in deaths to be coincidental and no substantial action was taken.

Reports by the nationwide MBRRACE-UK project found a neonatal death rate at least 10% higher than expected between June 2015 and June 2016. Additionally, the neonatal death total in 2015 doubled that of the previous year. The mortality rate had risen above what might be considered 'normal' rates. During a hospital visit in February 2016, The Care Quality Commission (CQC) was informed of difficulties in raising concerns with managers, but heard no mention of an elevated mortality rate. The CQC's report identified issues of "short-staffing" and "skill-mix" issues within the unit, yet it praised the overall positive culture of the trust, where "[s]taff felt well supported, able to raise concerns and develop professionally."

On 24 June 2016, following the deaths of two triplet babies on that day and the previous day, the lead neonatologist phoned the duty executive demanding that Letby be removed from the unit. The duty executive insisted that Letby was safe to work and that she was "happy to take responsibility" if anything happened to any more babies under Letby's care. In late June 2016, the trust's executive directors convened to address the question whether to involve the police. By this time, seven unexpected deaths had taken place within the unit. The belief among these executives was that the indications of Letby's involvement were largely circumstantial and they suspected certain doctors of embarking on a misguided "witch hunt". Moreover, they were concerned about potential harm to the Trust's reputation resulting from a police inquiry. Ultimately, they opted against engaging the police. The medical director and chief executive instead organised a review through the Royal College of Paediatrics and Child Health (RCPCH), which was initiated in September 2016. The unit's services were scaled back by hospital managers on 7 July 2016, cutting cot space numbers and no longer accommodating premature births before the 32-week mark.

The trust set a narrow scope for the review that excluded investigating Letby's actions or the deaths, but instead focused on the unit's general service. The RCPCH reported their findings to the medical director and chief executive in October 2016. They could not find a definitive explanation for the increase in mortality rate at the unit but found some insufficient staffing and senior cover. The report recommended a detailed case review of each death. The medical director asked neonatologist Jane Hawdon from Great Ormond Street Hospital to carry out the case reviews. Hawdon responded she could not conduct a detailed review because of lack of time but could provide a summary and did so after briefly reviewing the notes. She identified four cases that "potentially benefit from local forensic review as to circumstances, personnel etc". The board's chair at the time has said that he was misled about the scope of that review and its findings. Despite the thorough external independent review recommended by the RCPCH or the forensic review recommended by Hawdon, records of the hospital board meeting show the medical director telling board members that the RCPCH and Hawdon reviews concluded that the deaths in the neonatal unit were due to issues with leadership and timely intervention.

In September 2016, Letby raised a formal grievance about her late June 2016 transfer from clinical duties to the hospital's risk and patient safety office. This grievance was upheld by the board in January 2017, which determined her removal had been "orchestrated by the consultants with no hard evidence". They supported her return to the neonatal unit and offered her a placement at Alder Hey Children's Hospital in Liverpool plus support to develop advanced practice or a master's degree. The medical director also commented in the report that the trust's intention was to "protect Lucy Letby from these allegations". The chief executive had met with Letby and her parents on 22 December 2016 to apologise on behalf of the trust and assure them that the doctors who made the allegations would be "dealt with". He later ordered the consultants to send a letter of apology to Letby, which they did in February 2017.

In March 2017, consultants asked management to involve the police after receiving advice from the regional neonatal lead, who suggested further investigation was needed. They then met with Cheshire Constabulary on 27 April 2017, to raise their concerns, with Letby due to return to work on 3 May 2017. The trust publicly announced the involvement of the police in May 2017, stating this move was to "seek assurances that enable us to rule out unnatural causes of death." The investigation, designated Operation Hummingbird, lasted a year. Senior Investigating Officer Paul Hughes later said: "the initial focus was around the hypotheses of what could have occurred: so generic hypotheses of 'it could be natural-occurring deaths', 'it could be natural-occurring collapses', 'it could be an organic reason', 'it could be a virus', and then one of the hypotheses was that, obviously, it could be inflicted harm."

2023 trial
On 3 July 2018, police arrested Letby on suspicion of eight counts of murder and six counts of attempted murder. After Letby's arrest, police began investigating her entire career, including her time at Liverpool Women's Hospital. Letby was bailed on 6 July 2018, rearrested on 10 June 2019, and bailed again on 13 June. On 10 November 2020, she was arrested once again and denied bail. Letby denied all charges against her, and pointed to issues of hospital hygiene and staffing levels.

Letby's trial began at Manchester Crown Court on 10 October 2022 before Mr Justice Goss. She pleaded not guilty to seven counts of murder and 15 counts of attempted murder. Letby's parents and the families of the victims attended the trial.

The child victims were referred to as Child A to Child Q. The press secrecy around the identities of the 17 babies and nine colleagues who gave evidence was "rarely seen outside proceedings involving matters of national security." Two years before the criminal trial, Mrs Justice Steyn banned the identification of the living victims until their 18th birthdays. Several witnesses requested anonymity, including a doctor with whom Letby was said to be infatuated. The judge approved these requests, ruling that getting testimony from the colleagues was more important than them being publicly identifiable.

Evidence
The mother of one victim described hearing her infant scream, and walking in to find him with blood around his mouth and Letby in the room. She testified that Letby had attributed the blood to a nasogastric tube, saying "trust me, I'm a nurse." The baby's condition soon worsened and he died a few hours later.

Letby later sent a sympathy card to the parents on the day of the baby's funeral. Upon Letby's arrest it was found on her phone that she had photographed the card before she sent it and had still kept pictures of it. It was also revealed during the trial that Letby had to be told more than once not to enter a room where the parents of one of the victims were grieving. Letby told a colleague that taking Child A to the mortuary was "the hardest thing she ever had to do".

The Crown Prosecution Service cited texts sent by Letby to friends, describing them as a "live blogging" of events and as displaying "intrusive curiosity." Three days after the death of Baby A, Letby had messaged the manager of the unit offering to do more shifts, saying "from a confidence point of view I need to take an ITU baby soon X". Two days later she had a heated text exchange with a colleague over her manager refusing to let her go back onto the intensive care ward, and the next day, Baby C died. After the third baby death in a fortnight 2015, Letby replied to a text from a sympathetic colleague saying that she would "keep ploughing on" and added "I think there is an element of fate involved. There is a reason for everything". About two hours after the collapse of Child M, Letby sent texts reading: "Work has been shit but... I have just won £135 on Grand National!! [horse emoji]." and "Unpacking party sounds good to me with my flavoured vodka ha ha." Letby had also searched for the families of several infant victims on Facebook, including on the anniversaries of their babies’ deaths and on Christmas Day. The prosecution said that she would search for a number of them within minutes of each other, as if 'hunting for grief'. In total Letby had searched for 11 of the families affected.

The prosecution in Letby's case argued that suspicious incidents began in 2015, when Letby qualified to work with infants in intensive care, and that in April 2016, when the ward manager reassigned Letby from night shifts to day shifts, their distribution shifted accordingly.

A consultant testified that, in February 2016, he had walked in on Letby standing over a desaturating infant and failing to intervene. He said that Letby had responded to his questions by telling him that the infant had only just started declining. The infant in question survived the collapse.

All the babies involved had been expected to live and so their deaths came out of the blue. Previously, the majority of collapse in premature babies was expected or still medically explained if not. This was not the case for the recent cases.

Between March and June 2016 another three babies almost died while under Letby's care. Towards the end of June, she was helping care for triplets. All three had been in very good health and the deaths of two boys on consecutive days were causing staff considerable distress and shock, with the notable exception of Letby. This was not the first time that twins/triplets had collapsed within 24 hours of each other while under Letby's care, as a pair of twins had experienced collapses on consecutive days in August 2015. Only hours after one of the twins had died that month, the other became seriously unwell. During the police investigation and after analysis of a blood sample it was found that someone had intentionally poisoned the baby with insulin. This evidence had been missed for two years. The insulin, which had not been prescribed to the child, was identifiable as exogenous pharmaceutical insulin as C-peptide would be present in the specimen if the insulin had been produced by the baby. Laboratory analysis also showed that Child L had been poisoned with insulin. Hours later his twin brother, Child M, inexplicably collapsed while under Letby's care but managed to survive after thirty minutes of resuscitation. It was believed that Letby had injected air into the latter's bloodstream. The prosecution also noted that, although by this point she was not supposed to work night shifts, Letby was caring for Child L as she specifically volunteered to do an extra shift to care for her. Letby herself accepted at trial that the results showed that some victims had been deliberately injected with insulin and did not contest that someone must have administered it to them. Two of the medical expert witnesses described the insulin evidence as the "smoking gun".

A paediatrician testified that he and other clinicians had previously raised concerns about Letby, but were told by hospital administration that they "should not really be saying such things" and "not to make a fuss." Another doctor testified that Letby commented an hour before one victim died, "He's not leaving here alive, is he?" Although the consultants made their desire to have Letby removed from duties known to hospital staff after the triplet incident, this was refused and the next day another baby almost died under Letby's care.

Letby was the only staff member on duty for every one of the 25 suspicious incidents. After her removal from duty, and the downgrade of the unit, to concentrate on lower risk babies, no further incidents were deemed suspicious. Importantly, it was discovered that Letby had falsified patient records, covering her tracks by changing the times some babies collapsed to make sure she could not be placed at the scene. Criminal psychologist Dr David Holmes states that the varied methods she used to attack her victims, such as insulin and air injections and overfeeding milk, would all have been specifically chosen as things that would dissipate and not be easily detected afterwards.

Handwritten notes
Searches of Letby's and her parents' homes, and Letby's handbag, revealed a number of post-it notes handwritten by Letby. These included fragmentary phrases such as "help", "I'm sorry that you couldn't have a chance at life", "I don't want to do this anymore", "not good enough", "why me?", "I haven't done anything wrong", "we tried our best and it wasn't enough", "I am evil, I did this", and "I killed them on purpose because I'm not good enough to care for them". Another document that was presented said "I don’t know if I killed them. Maybe I did. Maybe this is all down to me".

The defence argued that the notes were "the anguished outpouring of a young woman in fear and despair", written while Letby was dealing with employment issues including a grievance procedure with the NHS Trust. The prosecution said that the notes expressed Letby's frustration at being removed from the neonatal unit. Letby herself denied that the notes were a confession, describing them as a reflection of her mental turmoil, written while she was being investigated.

The Guardian, in its reporting after the verdict, described the notes as "[t]he closest the prosecution had to a confession". The Telegraph highlighted one note which read "I'll never marry or have children, I'll never know what it's like to have a family", suggesting that Letby's fear of not having her own children might have motivated the killings.

Letby's diary was also found to be marked with the initials of the dead babies. Initials on those who had died were found to have been marked on the dates they were born, the days the prosecution alleged she attacked them, and on the days that they died.

Medical records
Searches of Letby's home found sensitive medical documents under her bed, including nursing handover sheets, resuscitation records, and blood gas readings. Of the 257 sheets, 21 related to infants Letby had allegedly harmed. Letby testified that she "collect[ed] paper" and had forgotten to remove the sheets from her pockets at the hospital; she also claimed that she could not destroy them, but a paper shredder was found in her home.

Letby's testimony
Letby herself gave evidence to the court in May 2023, breaking down in tears and claiming she was made to feel as though she were incompetent but "meant no harm." Letby said that the allegations had negatively impacted her mental health, saying, "I don't think you can be accused of anything worse than that. I just changed as a person, my mental health deteriorated, I felt isolated from my friends on the unit." It was also noted that she repeatedly contradicted herself, muddled up her story and became more and more frustrated with the prosecution's questions, which was unlike her usual calm demeanour.

Defence arguments
Letby's defence lawyer said that Letby was "a dedicated nurse in a system which has failed," that the prosecution's case was "driven by the assumption that someone was doing deliberate harm combined with the coincidence on certain occasions of Miss Letby's presence," and that there had been a "massive failure of care in a busy hospital neonatal unit – far too great to blame on one person." The defence argued that "extraordinary bleeding" in a baby boy murdered by Letby could have been caused by a rigid wire or tube. The therapeutic use of insulin was denied by Letby's colleagues.

Verdicts and sentencing
Final verdicts were returned by the jury on 18 August 2023. Letby was found guilty of seven counts of murder of seven babies. She killed them by injecting them with air, overfeeding them, poisoning them with insulin and assaulting them with medical tools. She is the most prolific serial killer of children in modern British history.

Letby was also found guilty of seven counts of attempted murder of six infants. Letby was found not guilty on two counts of attempted murder. The jury was unable to reach verdicts on six further attempted murder charges. Nicholas Johnson KC asked the court for 28 days to consider whether a retrial would be sought for these six counts.

On 21 August 2023, Letby was sentenced to life imprisonment with a whole life order, the most severe sentence possible under English law; she is the fourth woman in UK legal history to receive such a sentence. Goss said that Letby committed "a cruel, calculated and cynical campaign of child murder involving the smallest and most vulnerable of children." In closing, he stated, "there was a deep malevolence bordering on sadism [...] you [Letby] have no remorse [...] there are no mitigating factors [...] the offences are of sufficient severity to require a whole life order."

Letby opted not to attend the sentencing hearing and as such heard neither the various victim impact statements which were read out, nor her sentence being passed. In response, Alex Chalk, Secretary of State for Justice, wrote that the government will "look at options to change the law at the earliest opportunity" to compel defendants to attend their sentencing. On 30 August 2023, Prime Minister Rishi Sunak announced that the UK government would introduce legislation to Parliament that would compel convicted criminals to attend their sentencing hearings, by force if necessary, or face the prospect of more time in prison.

After the trial, Letby was transferred to HMP Low Newton, a closed prison for women in County Durham. , Letby is being held in HM Prison Bronzefield.

Motives
The prosecution in Letby's case suggested boredom, thrill-seeking, and "playing God" as possible motives for the killings. They also alleged that Letby had a secret relationship with a married doctor involved with some of the cases. As evidence, they cited Letby's frequent texts to him on certain night shifts, as well as a piece of paper from Letby's office where she had written phrases including, "I trusted you with everything and loved you", "you were my best friend" and "please help me". Letby denied all these suggestions, including the idea that she had a relationship with, or crush on, the doctor in question.

The former detective who acted as lead investigator on the 1990s Beverley Allitt case drew parallels between Allitt's and Letby's cases, suggesting that Letby might have copied Allitt's methods. Criminal psychologists Dominic Wilmott and David Holmes suggested that Letby may have been motivated by factitious disorder imposed on another, a theory also proposed about Allitt. 31:15

David Wilson, an emeritus professor of criminology, published an August 2023 opinion piece in The Guardian argued that Letby was driven by a "hero complex". Later that month, Wilson discussed Letby on Newsnight, where he argued that healthcare killers join the profession in order to target vulnerable victims, such as the very old or very young.

Disciplinary action
On 13 March 2020, while out on bail, Letby was placed on an interim suspension by the Nursing and Midwifery Council. On 18 August 2023, Andrea Sutcliffe, Chief Executive and Registrar of the Nursing and Midwifery Council, stated that Letby "remains suspended from our register, and we will now move forward with our regulatory action, seeking to strike her off the register". Letby was removed from the nursing register on 12 December 2023, having informed the Nursing and Midwifery Council that she did not accept guilt but did not contest the removal.

Appeal
In January 2024, Letby applied to the Court of Appeal for permission to appeal her convictions, which a judge refused. Letby renewed her application and at a three-day hearing in April 2024 her lawyers put forward four grounds of appeal concerning the trial judge's refusal of applications, but in May 2024 the three judges of the Court of Appeal refused permission to appeal.

As part of the appeal Letby's counsel Ben Myers again tried to question the inclusion of evidence by Dr. Dewi Evans, the prosecution's lead witness, saying it should have been disallowed as evidence as he had been "dogmatic and biased". The appeal judge rejected these criticisms, ruling that it was incorrect to state the Evans lacked impartiality and that he indeed was well-qualified to give an opinion. The appeal judges were of the view that it was up to the jury to assess the quality of Evans' evidence.

A second ground for appeal was that the medical evidence that Letby had fatally injected air into babies’ bloodstreams was "very weak", whilst the third ground was that the judge had been wrong to direct the jury that they could could convict even if they were unsure of the precise method used by Letby for every case. The final ground was that the judge had failed to investigate the impartiality of one of the jurors. All of these four grounds were refused by the Court, with the judges' subsequent written statement concluding that the trial had been "thoughtful, fair, comprehensive and correct" and that none of the four legal challenges advanced by Letby were "arguable", saying that the criteria for the admission of fresh evidence had not been met.

Retrial
At a hearing on 25 September 2023, the CPS confirmed that there would be a retrial on one of the six counts of attempted murder against Letby on which the jury at the original trial could not reach a verdict. This was not to start until after judges had decided whether or not to grant Letby permission to appeal against her existing convictions.

The retrial started on 10 June 2024. The prosecution asserted that the child, 'Baby K', repeatedly deteriorated when left alone with Letby, despite the previous nurse testifying that the baby's condition seemed stable when she left him. The consultant on duty that night was Dr Ravi Jayram, and he alleged that he had gone into the nursery to reassure himself that the baby would be okay in Letby's care, only to supposedly find Letby standing next to Baby K's cot and not doing anything or calling for assistance while the infant was desaturating. It was established that the desaturation had been caused by the child's breathing tube becoming dislodged, and this happened again twice in the next few hours, which the prosecution asserted occurred when Letby was present.

On 2 July, Letby was found guilty of attempted murder, and on 5 July 2024 was sentenced to another whole-life order.

Further investigations
Following the verdict, it was reported that police were investigating whether Letby harmed other babies. There was a continuing investigation of incidents which detectives had identified as "suspicious" at the Countess of Chester Hospital involving around 30 other infants. Neonatologists looked into about 4,000 admissions at the hospital and Liverpool Women's Hospital, where Letby had worked from 2012 to 2015, and were to pass on any cases of "unexpected and unexplained" deteriorations to police. At least one family was told by police that the birth of their child at the latter hospital was part of the enquiry. Cheshire Police have said that further charges could "possibly" be brought against Letby as a result of these further investigations.

On 4 October 2023, Cheshire Constabulary announced an investigation into corporate manslaughter at the Countess of Chester Hospital.

Thirlwall inquiry
After Letby's conviction the British government ordered an independent inquiry into the circumstances surrounding the murders. The Department of Health and Social Care said the inquiry would examine "the circumstances surrounding the deaths and incidents, including how concerns raised by clinicians were dealt with." It was affirmed that the inquiry would be non-statutory, so witnesses could not be compelled to give evidence and inquests would still be necessary. The trust's medical director, chief executive and the nursing director at the time of the murders all commented they would fully cooperate with the inquiry. The medical director retired in August 2018 and the chief executive resigned in September 2018 after signing a non-disclosure agreement.

Slater and Gordon, a law firm representing two of the victims' families, issued a statement calling for the inquiry to have the power to compel witnesses to participate, since a non-statutory hearing "must rely on the goodwill of those involved to share their testimony." The need for a statutory inquiry was a view echoed by, among others, Sir Robert Buckland, former Secretary of State for Justice, Samantha Dixon, MP for the City of Chester, Steve Brine, chair of the House of Commons Health and Social Care Select Committee, Sir Keir Starmer, Leader of the Opposition, and the Parliamentary and Health Service Ombudsman.

The education minister Gillian Keegan said that the type of inquiry would be reviewed after the chair was appointed. On 30 August 2023, Health Secretary Steve Barclay announced that the inquiry had been upgraded to a statutory inquiry, describing it as the best way forward and meaning that witnesses would be compelled to give evidence.

Lady Justice Thirlwall was appointed to chair the inquiry. The terms of reference of the inquiry were published on 19 October 2023 and updated on 22 November 2023, when she formally opened the inquiry.

The inquiry will be held in public. Following submissions the Chair ruled on 29 May 2024 that remote live viewing would be available to the Core Participants, their legal representatives and the media but that livestreaming "to the world at large" would not.

Calls for regulation and reform
The British Medical Association, which represents doctors, called for a process for NHS managers and healthcare administrators to be held accountable for mismanagement, in a similar way to how the General Medical Council may strike off doctors who harm patients. A neonatal consultant who alerted administrators about his suspicions about Letby also called for regulation of healthcare management.

The Parliamentary and Health Service Ombudsman Rob Behrens, called for radical change to NHS management in order to prevent future similar occurrences.

Doubts about the conviction
Some of Letby's friends and former colleagues continue to believe in her innocence. After the verdict, speculative theories circulated on the internet doubting the outcome. The Letby case has attracted amateur investigators who believe that there may be evidence suggesting that a miscarriage of justice has taken place.

Statistician Richard D. Gill and lawyer Neil Mackenzie KC, who co-authored a work with others on the use of statistics in court cases, have also questioned the outcome. In May 2024, The New Yorker published a feature article by staff writer Rachel Aviv that questioned Letby's conviction. Aviv pointed to pervasive staffing shortages and argued investigators had used flawed statistical reasoning and this amounted to a Texas sharpshooter fallacy. Aviv also questioned the testimony of Dewi Evans, commenting that a report by Evans as an expert witness in a previous case had been deemed "worthless" and said to have included opinions that were "tendentious and partisan" and "outside Dr. Evans' professional competence" by a Court of Appeals judge. Due to reporting restrictions imposed as a result of Letby's impending retrial, the online version of the article was disabled for British readers, a decision which was questioned in Parliament by the Conservative MP David Davis. The issue of The New Yorker 's print edition that contained the article was, however, available for sale in British newsagents as usual.

In July 2024, The Guardian published a similar feature article by special correspondent Felicity Lawrence, exploring in further detail many of the contentious points raised previously. Lawrence said that "there was no forensic evidence to prove her guilt and no one saw Letby – who continues to maintain her innocence – causing harm". She also scrutinised the use of statistics in the trial, the accuracy of the air embolism diagnoses, and the insulin evidence. The Daily Telegraph also published an article in July 2024 casting doubt upon Letby's murder conviction, arguing that the babies who died were already in poor health due to their prematurity and that this may better explain the deaths. Spiked magazine columnist Luke Gittos criticised those questioning Letby's conviction, saying that Letby herself had accepted that some babies had been poisoned with insulin.

Dewi Evans has said that he has received abuse by Letby's supporters online who doubt the safety of her conviction. He has argued that people find it difficult to accept that a killer could be a "young, white, English nurse from a respectable background". In an opinion piece for The Observer, columnist Martha Gill responded to those doubting whether she could be a killer by saying "Letby fits the profile rather well", concluding that "the nurse’s case shows the dangers of believing that women like her could not possibly commit murder".

In a BBC article specifically about reactions to Letby's conviction and doubts about her conviction, it was noted how barristers of the families had responded to this at the early stages of the Thirwall Inquiry into Letby's crimes by speaking of the anguish pro-Letby campaigns had caused, with Peter Skelton KC arguing: "Lucy Letby's crimes, in particular, continue to be the subject of such conspiracies, some of which are grossly offensive and distressing for the families of her victims". In response to these doubts of Letby's conviction, these barristers argued for the inquiry to be publicly livestreamed, with Richard Baker KC asserting: "They are toxic, they are often ill-informed, and they ultimately grow in the shadows. The more light that we put on this Inquiry, the less space there is for speculation and conspiracy". However, the inquiry was unconvinced and rejected this. The BBC commented that reporting restrictions had left an "information vacuum" which "the internet has happily filled".

Other developments
Dewi Evans has called for an investigation into the possibility of charges of corporate manslaughter in relation to the Letby case.

The Royal College of Paediatrics and Child Health stated, "We must learn from these crimes and how Lucy Letby was able to bring harm to these babies so that no situation like this can ever happen again" and welcomed the independent inquiry. NHS England's Chief Nursing Officer Dame Ruth May issued a statement saying, "The NHS is fully committed to doing everything we can to prevent anything like this ever happening again, and we welcome the independent inquiry announced by the Department of Health and Social Care to help ensure we learn every possible lesson from this awful case."

On 21 August 2023, it was announced that the nursing director at the Countess of Chester Hospital at the time Letby was based there had been suspended from her job as a senior nursing officer at Northern Care Alliance NHS Foundation Trust with immediate effect, because of information that came to light during the trial. The Nursing and Midwifery Council subsequently announced she would face an investigation into her fitness to practice. She and other executives at the hospital have been accused of ignoring warnings about Letby.

It was reported that the British government were examining how Letby's pension can be stopped. The NHS pension scheme regulations provide for a forfeit of pensions after a conviction of certain crimes.