Lucy Letby didn’t murder the babies, a new report shows. Now, Alasdair Millar calls for profound reforms from police culture and a CCRC, to reduce wrongful convictions, as he writes in Quadrant (August 18, 2025)
Letby, a nurse convicted in 2023 of seven murders and fourteen attempted murders at the Neonatal Intensive Care Unit at the Countess of Chester Hospital in Cheshire. Letby was sentenced to fifteen whole-of-life prison sentences, indicating that she will spend her entire life behind bars without hope of release. Two appeals against her conviction (the maximum allowed) have been rejected. However, a recent report from fourteen internationally renowned neonatologists and paediatricians argues that she is innocent of all charges, that no crimes were committed, and that the deaths and deteriorations observed in the alleged attempted murders were due to natural causes complicated by various human factors.
Letby worked in the unit from 2012 to 2019. The deaths for which she was found responsible occurred from June 2015 to June 2016. No accusations were levelled for any other period. The details of the alleged murders are contained in the final judgment7 and in articles in the lay press including one published this year in the New Yorker.
I concentrate here on the quality of the evidence.
First, the case was entirely circumstantial. There was no witness to any of the alleged attacks. The murders were said to arise by injection of air into the veins or stomach (air embolism; five cases), or by insulin (two cases). Both methods are indeed potentially fatal, and insulin as a murder weapon has precedent. However, the presence of air in the bloodstream can arise from other causes. In neonates, air embolism is usually (in 80 per cent) associated with cardiorespiratory resuscitation (common in neonatal ICUs), but can also arise from inadequate flushing of air from syringes, surgery including radiological procedures, or infections with gas-forming bacteria. The amount of air required to cause severe injury in premature neonates is very small.
Second, a 1989 paper on neonatal air embolism was presented by the prosecution, but the paper’s author, Professor Shoo Lee, did not give evidence and subsequently claimed his paper was misrepresented.
Third, the presence of higher than expected insulin levels, initially used as evidence of insulin administration, has been re-interpreted on biochemical grounds relating to unsuppressed levels of the compound C-peptide (which is secreted along with insulin, and suppressed when insulin is injected) to negate the conclusion that insulin was administered.
Fourth, the expert medical evidence at the trial was that death in the babies had no medical explanation, which allegedly left only murder as the cause. This is illogical and erroneous, as has now been shown in the Folbigg case.
Fifth, the police presented a table showing that Letby was the only nurse on duty at the time each baby was assaulted. This evidence would have weighed heavily with a jury but is regarded as invalid on statistical grounds. Letby was rostered on more frequently than other nurses, and the list did not include other babies who died when Letby was not present.
Last, police searched Letby’s home and found a scribbled sheet of paper containing the words “I killed them on purpose because I’m not good enough to care for them”; “I AM EVIL I DID THIS.” This was also highly incriminating, but is now reported as having been generated during a session with a psychologist, and one plausible interpretation is that Letby blamed her imagined personal inadequacies for the high number of deaths in the unit.
Evidence was also drawn about the poor physical state and inadequate size of the hospital, the inadequacy of the ICU, poor hospital management, the introduction of relatively unqualified nurses replacing experienced nurses leading up to the year of the “murders”, and friction between nursing and medical staff. It is also relevant that neonatal intensive care units care for premature as well as full-term patients who are dangerously ill. Consequently they experience high and variable mortality rates, and are stressful worksites.
The panel unanimously concluded that every death … was due to natural causes
No further appeal is open to Letby, but the new information on the case has been submitted to the Criminal Cases Review Commission, which was created in the UK in 1995. The CCRC has the power to send a case back to the courts for reconsideration in the light of new evidence. The new information in the Letby case is the report by the fourteen internationally renowned paediatricians and neonatologists, who studied the cases on the suggestion of Professor Lee. The summary report has been published. The panel unanimously and sensationally concluded that every death and case of deterioration was due to natural causes. In effect, they declared Letby innocent of all charges. The summary report gives reasons for these findings in seven selected cases. The panel also laid blame on several contributing factors: the poor physical state of the hospital, understaffing, and inadequate medical performance were contributing factors to the deaths. The full report has been submitted to the CCRC and is not yet publicly available.
The important background issues remain. How do miscarriages of justice arise and what can be done to minimise them? I shall start with the UK broadcaster Ludovic Kennedy, who was born in Edinburgh in 1919 and died in 2009 after an illustrious career as journalist, broadcaster, humanist and author. He was to me a familiar television face as a newsreader and presenter of the BBC TV flagship Panorama (the UK equivalent of Four Corners). In the 1950s and 1960s he campaigned against the death penalty, stimulated by the case of Timothy Evans, who was wrongly hanged for two murders committed by his neighbour.
Kennedy became concerned with the wider phenomenon of the miscarriage of justice and its causes. His interest was sustained over decades and culminated in his book 36 Murders and 2 Immoral Earnings, published in 2004. He argued that the high rate of miscarriages was a result of the adversarial system used in criminal court cases in the Anglosphere, in which prosecution and defence teams lead evidence and cross-examine in front of a judge and jury. He concluded that the so-called inquisitorial system (by a magistrate or judge without a jury) as used in continental Europe, was to be much preferred.
Kennedy had presented these arguments in Australia almost two decades earlier, and published an article in Police Life (published by the Victorian Police) in 1986. That article, now difficult to obtain, was referred to and answered in turn by Justice Michael Kirby. Kirby called Kennedy’s proposals a “dazzling dream”. He expressed concerns that confidence in a magistrate or judge to always remain neutral was misplaced, and that the proposals would alter the balance of power in favour of the state against the accused individual and thereby dilute protections under law. More recently, Kirby has published his responses to recent wrongful convictions in Australia including the Folbigg and Pell cases, and clearly his views have altered little. In both papers he states that no system of justice is perfect or can be made perfect. This is of course true but it must not be conveyed in such a way as to imply that wrongful convictions are tolerable because they are inevitable. An important objection to Kennedy’s solution arises from the significant number of miscarriages of justice in Europe (see above) where jury trials have been largely abandoned. Thus his suggested alternative system does not prevent wrongful convictions.
Preventing miscarriages of justice depends on the availability of good data on how the cases arise. Unfortunately this is hampered because there is no single international definition of “miscarriage of justice”, no standard procedure for collecting data, and no standard method of analysing deserving cases after exhaustion of appeals. Australia does not have a last-resort review committee, unlike the UK (the CCRC) and New Zealand, a circumstance noted by Kirby. A related problem in this area is the lack of a legislated method (except in the ACT) of assessing entitlement or amount of compensation for wrongful prosecution and incarceration. All other states and territories rely on ex gratia payments.
Prevention depends on minimising the possibility of each known cause, logically starting with the most common. However, data on the relative contribution of the known contributing factors are not collected routinely, and are not available on an internet search. I extracted the reasons for miscarriages given in cases listed in Wikipedia including short summaries, restricted to cases arising in Australia, New Zealand and the UK, which have similar criminal justice systems. This list “includes cases where a convicted individual was later cleared of the crime and either has received an official exoneration, or a consensus exists that the individual was unjustly punished or where a conviction has been quashed and no retrial has taken place, so that the accused is legally assumed innocent. This list is not exhaustive.” It was updated as recently as April 15.
The list provided seventy-three cases, excluding the fifty-nine prosecutions in the Post Office scandal (listed as one case) which is reminiscent of the Robodebt case in Australia. Where the reason for the miscarriage was not clearly listed, I inspected primary reports. The results are shown in the table below. These data should be taken as general trends only, because the Wikipedia database may be incomplete. For example, the Folbigg case is not listed but was included in the analysis. The results clearly suggest a disappointing tendency for police malfeasance as the most common contributor.
Though never acceptable, the irregularities vary in their severity, and in extreme circumstances such as the troubles in Ireland or the 1985 Tottenham riot which resulted in the murder of a young police constable, are even perhaps understandable though nevertheless wrong. When emotions run high, the need for restraint becomes mandatory. The data also point to a need for improved procedures to reduce the potential for flaws in forensic evidence.
Though it is of course correct to reverse a guilty decision when new technology exonerates the accused, the term “miscarriage of justice” is always retrospective, and the original trial might in fact be beyond criticism. Reliance on flawedexpert opinion is also an area of risk, as shown by the faulty evidence from Sir Roy Meadow and Dr Martin Ward-Platt in three cases of alleged murder of children by their mothers that was rejected on appeal. Ward-Platt was listed to be a witness at Lucy Letby’s trial but died beforehand. There is an implication that prosecutors know which expert witnesses to call to obtain testimony known to support a guilty verdict. An incidental finding of my analysis was that the average duration of incarceration before the wrongful verdict was discovered was 10.8 years, but was fifteen years or more in nineteen cases. This is a tragically high human cost.
Miscarriages of justice arise from the complexity of criminal law and procedures, and the way that this system interacts with the imperfect actors involved: judges, legal representatives, officers of the DPP, police, jury, witnesses, the accused and news media. Shakespeare declared “All the world’s a stage”, but no part is more so than inside a criminal court in session. The subject matter generates emotional extremes. Some actors intend to tell the truth, and some wish to obscure it. Some claim expertise but may present untrue testimony which they believe is correct and which is accepted on the basis of their qualifications and reputation. All may exhibit shortcomings of human behaviour that may be inconsequential outside the court but can obscure important truths inside. Some exhibit unethical behaviour in generating false evidence.
So, yes, there are many ways a miscarriage can arise, and in that context they do appear inevitable. But surely we can reduce the rate? As a layman, it appears to me necessary to construct stronger rules of evidence to expose faulty testimony or wrongly presented forensic data at a trial, and perhaps strengthen further the procedures for appeals. My data suggests that substantial cultural changes are required by the police in each of the three jurisdictions studied, and probably
elsewhere. In the past few weeks, as part of the Lawyer X scandal in Victoria, a convicted criminal has been released because his trial was tainted by an improper secret association between the police and the accused’s solicitor. Our guardians of the law should know better. In the light of such cases it is naive to believe that police malfeasance is limited to only those cases that lead to a successful appeal.
I am under no illusions that reducing the incidence of miscarriages of justice will be easy. Each suggested improvement will require deep thought to exclude unintended consequences, but this does not apply to two obvious possibilities, namely to establish a federal Criminal Court of Appeal, and an Australian CCRC (also federal) with power of referral to state and territory criminal courts. The ex gratia system of compensation provides highly variable and often politically determined relief, and a legislated system of compensation in both Australia and New Zealand is desirable. This is not intended to suggest that every victim deserves compensation, because innocence does not always follow in cases of wrongful imprisonment, and in some appears unlikely.
Finally, returning to the yet-to-be-resolved Letby case, the mounting criticism of the evidence given at her trials and the recent report of fourteen international experts6 surely cast strong doubt on the trial verdicts. In other words, if the international report is accepted, the “beyond reasonable doubt” threshold required for a guilty verdict has not been met. The corollary is that the presumption of innocence applies. (Note: citations have been omitted.)
Alasdair Miller is a retired physician and clinical pharmacologist who lives in Denmark, WA.
This not the first investigation that challenges the Letby conviction we have published:
Lucy Letby: Did she do it?
Lucy Letby – serial baby killer or wrongfully convicted nurse?
