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The timing of this week’s public inquiry into “the events at the Countess of Chester Hospital”, and the growing suspicion that Lucy Letby’s convictions are unsafe, inadvertently throws up a dramatic forking of two possible worlds. In the first, the nurse committed some of the most depraved crimes in British history, murdering seven premature babies in her care and attempting to kill eight others. If this is indeed the truth, few should shed any tears over her incarceration, and the inquiry will be essential to understanding how systems at the hospital enabled her behaviour.
Yet in a second scenario, the same woman is the innocent victim of catastrophic bad luck and other people’s bad judgement. Babies still died tragically and perhaps also preventably, but nobody deliberately killed them.
In this version of events, Letby is stuck in a Kafkaesque nightmare: first ostracised and nicknamed “Nurse Death” by colleagues because of her coincidental presence at several fatalities on the ward; then wrongly convicted, partly on the basis of a private “confession” she was encouraged by a therapist to write down in order to deal with mounting anxiety; and finally, the subject of hundreds of lurid headlines about being a “monster”, with her family and personal life raked over gleefully by the press.
In this possible world, her sentencing — 15 whole life orders without possibility of parole — is one of the gravest miscarriages of justice in British history. And in this hypothetical case, the public inquiry now happening is not only a waste of money but may well lead to policies that are not fit for purpose, since they are predicated on false assumptions.
One is left wondering how there can possibly be a fruitful public inquiry into events whose very existence has become so highly contested. The New Yorker kicked things off with a sceptical investigation into the case back in May. This questioned the prosecution’s exclusive dependence on circumstantial evidence, its unorthodox interpretation of several sets of statistics, and the admission of what may have been faulty insulin tests as evidence. A further point concerned the testimony of a key expert witness for the prosecution, Dr Dewi Evans. Evans’s theory about how Letby supposedly harmed seven of her victims — namely by injecting air so as to cause embolism — was accepted by the jury, and yet has since been dismissed by several others in the same field as implausible.
It is hard to fully imagine the agony of the parents of the infants involved: first believing the death of their precious child to be the result of natural causes, and grieving accordingly; then being forced to come to terms with the horrifying idea that death was maliciously caused by a caregiver they had liked and trusted; and now flung back into a purgatorial space where they don’t know for sure which of these outcomes is real. Small wonder, then, that the parents of one such deceased baby have rejected the speculation about the safety of Letby’s conviction outright, calling it “lies and misinformation” that “makes us sick to our cores”.
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SubscribeThe thing is, to be found guilty of murder, it needs to be proven beyond reasonable doubt. That’s the law. A foundational principle of the law in a free country.
Whether or not Lucy Letby is guilty I have no idea.
But the whole reason this discussion is ongoing is that there is clearly ‘reasonable doubt’.
And if there is, she shouldn’t have been found guilty. That’s a legal principle we need to fight very hard to keep.
Rubbish. The standard of proof beyond reasonable doubt applies to the jury who hear all the evidence, not to people who weren’t there giving the world the benefit of their ignorance.
Yes, journalists and relevant experts are entitled to examine the evidence and express an opinion, and interested parties can petition the relevant authorities. That could lead to an appeal or a retrial which reaches a different verdict, but random public comment doesn’t in itself establish reasonable doubt.
The trouble is that there is a precedent, the Sally Clark miscarriage (and others). Expert evidence was very seriously flawed and the jury’s understanding of the statistical ideas, limited.
Statistics is far harder to understand than we give credence for; in the Sally Clark case it took the evidence of the Royal Statistical Society to over turn the verdict.
Yes, outsiders should trust juries. Yes, the strong statements on either side are unhelpful but there is a chance of a terrible miscarriage of justice. After release Sally Clark turned to the bottle and dies soon after
Except here there is a lot more evidence than just statistics; which was not so in the dreadful Clark case
Well yes, the prosecution’s theory of death rested on the rather inexpert evidence of a medical person who volunteered an unsupported narrative of death by air injection. For its own reasons the defence did not call its own expert witness. So, on both sides, it is not “just statistics”.
Murder by air embolism has happened — look up Ivo Poppe and William Davis — but occurrences are few and far between. That alone justifies skepticism. What evidence of air embolism was there in the autopsies — or, because these were hospital deaths of high-risk infants, was there no autopsy done?
Although you base your argument on the supposed misunderstanding of statistics, you don’t see the complete fallaciousness of arguing that because other cases were miscarriages of justice, this case is too.
The key difference with the use of statistics in the Sally Clark case is that the statistics were relied on to establish that homicide had occurred in the first place – it was said that it was so statistically improbable that multiple instances of SIDS could occur in one household that they must have been deliberate killings.
In Letby’s case, the statistics were used to show the unlikelihood of there being another person responsible for the harm which befell the babies, and formed only one element of the prosecution’s circumstantial case. Notably, her defence team did not raise these statistics in her appeal to the Court of Appeal.
Its not merely random public comment though is it. Recognised experts have cast doubt on the evidence and explained why they have doubts.
True. I’m happy to hear from any genuine expert, as the second part of my comment indicates. But I was criticising Seb Dakin’s random public comment.
Fellows of the Royal Society of Statistics will be tickled to read they are guilty of making random public comments.
I didn’t say they were. I said Seb Dakin was.
And they are going for an appeal? So what’s your point? And Sally Clarke?
Sorry, but I don’t understand your comment.
Is anyone denying the fact that her notes were written as a therapeutic exercise and then obviously mis-represented as a confession? Or did the judge decide not to let the jury know? “All the evidence’ is often just all the evidence the judge chooses. The prosecutor has behaved vindictively and very immorally. Is he a man you would trust?
Anyway, the babies are gone. It’s a terrible tragedy. But this woman is facing life in prison. Every moment for forty or fifty years. If she is innocent that makes two tragedies. And a serious offense against our rights living in a nation devoted to “the rule of law”. Or is the UK devoted to the lawyers and judges. But not the law.
Your questions all seek a conclusion which may or may not be correct, and which can only be determined either way by examining all the evidence. Have you done that? And even if you have, that’s irrelevant to my original comment, which was deprecating Seb Dakin’s stupid rendering of the concept of reasonable doubt.
Lucy Letby may be innocent. Better-informed people than Dakin, me, and perhaps you should make that decision.
Which is precisely why an appeal, with *all* the evidence, and a range of expert opinion, is required. It helps no one and nothing: grieving parents, Letby, the judicial system, the NHS, that the fullest picture has not been fully scrutinised.
You’re begging the question. The problem is that the people of the jury didn’t hear all the evidence, and that’s why an appeal is necessary. Barring some “smoking gun” evidence that conclusively confirms or refutes her conviction, only Letby knows what really happened (or didn’t).
Totally agree Doctor Stock.
The gravity of the situation demands that any and all serious advocates should be indulged.
For my tuppenceworth, I don’t believe she’s guilty.
https://www.spiked-online.com/2024/08/30/the-case-against-lucy-letby/
When I read the statistical argument in the original piece I thought maybe there had been a mistake to convict her, but the more I’ve read the more I believe she committed the murders. Obviously the only one who knows for certain is Letby but to me the evidence against her is pretty damning
I agree. There has been a recent spike in sudden deaths in the area where I practice as a GP. But they were all men in their 40s or 50s who smoke and drank, had family histories of cardiac disease and hadn’t been tested for hypertension or raised cholesterol. Family and friends all reported that they complained of chest or back pain shortly before collapsing. It’s such a common picture that the coroner didn’t even want autopsies, preferring to concentrate on the arduous paper work for the equally common domestic and sexual violence cases which demand lengthy court appearances. Common things occur commonly. The deaths of these babies were an anomaly in that there was no preceding organic illness apart from prematurity. They were mostly off ventilation and doing well prior to a sudden collapse. That doesn’t tend to happen in intensive care units- patients are so closely monitored that any worrying changes in their condition is picked up early. We are taught in medical school to go through all the major pathological processes when considering a diagnosis- Infection, neoplasm, vascular, immunological, trauma, toxicity, metabolic, degenerative, congenital, metabolic and endocrine. For these babies to all suffer from signs of trauma or toxicity in a setting where this don’t usually happen is probably what influenced all the medical experts in this case to suggest foul play.
Forgive me, I do not presume to question your knowledge but isn’t there a difference between being unable to explain something and suggesting murder?
It’s not a good enough reason to convict someone
Feel free to question my knowledge. Medicine is full of uncertainty and questioning each other is vital to prevent misdiagnoses and harmful treatments. Believe it or not we have learned from the days of blind obedience to the authority of our elders.
But the point of my example of a cluster of cardio-vascular deaths is that we had lots of evidence to back us up. As well as lots of opportunity to question witnesses, relatives and other clinicians to check our tentative diagnoses with. There are several details I missed out of the example. Indigenous males have high rates of heart disease at all ages from teenage years up. Several have died on on football fields, which prompted the research that found younger age not to be a protective factor. Most of them were exerting themselves in 36^C + heat, one changing a tyre another driving a grader. And so on and so on. All the deaths were discussed extensively afterwards to see what we could do to prevent more. It adds up to a model of health care which, while not being infallible, is still more trustworthy than ever before. I would trust my health to this system, even though there is a small chance my treatment might be unintentionally wrong.
We just don’t have all the details of the Letby case in the public domain. The vast number of professionals who have gone into all the nitty gritty details of the case presented them to a judge and jury who considered and weighed up the evidence, convicting her of some of the deaths, but not others where the evidence was not so strong. It’s a system that is not infallible, but probably safer than the days of the Guildford Four, Sally Clark etc that other posters have brought up. It’s important to keep questioning. But would you trust this process if you were accused of a crime? If not, which process would you prefer? Would you trust your premature baby to a unit with Letby working in it knowing that some of her workmates didn’t trust her? On the partial evidence I’ve seen I don’t think I would.
In her situation being accused of such of such heinous crimes, and being truly innocent of every charge – you would be outraged, fighting for your corner in disbelief, displaying true sincerity and empathy towards the families about what they were going through. There is a reason why none of this was observed at the trial. And what would possess a truly innocent person to write down on a piece of paper well in advance of being arrested, that I’m evil and I did this’
The Jury who made the decision to convict sat through months of evidence .. clearly mounting evidence, – beyond reasonable doubt evidence.
“what would possess a truly innocent person to write down on a piece of paper well in advance of being arrested, that I’m evil and I did this’”
Perhaps the state of mind so familiar to us from the history of religion, where people become convinced that they are miserable sinners, responsible for all sorts of evils, when to an outside observer they are obviously not.
I have no opinion (due to inadequate knowledge) of the Lucy Letby case. But I find the miscarriage of justice interpretation perfectly plausible.
Facts:
(A) Prior to her placement at the Countess of Chester, Letby is understood to have carried out two work placements at the Liverpool Women’s Hospital between October and December 2012, and January and February 2015. An audit carried out by Liverpool Women’s Hospital recorded that whilst Lucy Letby was working there, dislodgement of endotracheal tubes occurred in 40% of shifts that she worked. “It generally occurs in less than 1% of shifts.
(B) During the period of time at Countess of Chester Hospital when Letby was accused of these terrible crimes, she was strikingly present on shift at an alarming rate of baby deaths and near fatal collapses.
(C) – Notes written down by Letby discovered by police after her arrest to the effect of ‘Im evil, I did this’
(D) Since Letby left the hospital’s neonatal unit, there has been only one death in seven years.
A+B+C+D = very disturbing
1. “The deaths of these babies were an anomaly…” not in a hospital with a poor track record. “… what influenced all the medical experts in this case to suggest foul play.” as opposed to systematic or other failures in the hospital (aka arse covering).
2. “When I read the statistical argument in the original piece I thought maybe there had been a mistake to convict her…” I agreed with you up to that point, but I’ve stayed with that position. I’m genuinely interested to see the statistics (with the outlined challenge as per the expert article below) that made you change your mind to say she committed the murder?
I would refer both my points above to a read of:
https://www.telegraph.co.uk/news/2024/07/09/lucy-letby-serial-killer-or-miscarriage-justice-victim/
I find the Spiked article entirely unconvincing. It is quite clear that the jury were led up the statistical garden path – whether the judge was equally fooled or had been informed that a guilty verdict would be in the public interest, I would not like to say. Perhaps both.
So we’ll ignore the fact many colleagues had concerns about Letby (although originally through malpractice rather than murder), we’ll ignore the times she was the ONLY nurse on duty when these babies went downhill for no obvious reason, we’ll ignore her rambling confessions in her diary, falsifying records and odd behaviour etc. There was much more evidence presented than just the statistics
Prof. Stock’s arguments come perilously close to arguing that trying to determine someone’s guilt or innocence in a court of law is a waste of time – except in the most open-and-shut cases.
Lady Thirlwall is quite right. The commentators weren’t at the trial. The judge and jury were. Unless the commentators can point to a biased trial or perjured evidence, there is no case to answer. Letby’s trial bears no relation to the trials of the Birmingham Six or the Guildford Four.
Fortunately for victims of miscarriages of justice, and despite your apparent confidence, those aren’t the only grounds on which a conviction may be deemed unsafe on appeal.
You’re right. Fresh evidence might come to light. In this case, I understand that there is no fresh evidence.
Tell that to the eminent statisticians and scientists who weren’t called to give evidence – part of the problem is the very fact that they ‘weren’t at the trial’.
The defence could have called any number of expert witnesses, but chose not to. Given that no one in these comments seems to have a background in criminal law I think Lady Justice Thirlwell’s remarks are highly apposite.
“The defence could have called any number of expert witnesses, but chose not to.”
That could mean essentially opposite things.
Could be that all the experts they consulted told them that the prosecution evidence was sound.
Could be they didn’t do their job properly.
It may well be the former. But if it’s the latter, it wouldn’t be the first time.
Are you ( and Lady Thirlwall ) saying that if the commentators had been at the trial they would have felt the agony of the families and would have understood that a witch had to be found and burned for the public good?
No. The agony of the families is irrelevant. Any undue attempt to sway a jury’s emotions should be jumped on by a judge.
What is relevant is hearing the evidence from the witnesses (including Letby), and that includes the demeanour of the witnesses. It’s how we all judge if another human being is telling the truth or not.
What shouldn’t be lost in this debate is the fine analytical skills brought to bear on this matter by KS, especially around the linkage with free speech.
As a professional philosopher, she does best when applying those skills rather than delving into matters of cultural and/or social concerns as with her “vanilla sex” essay.
Always interesting to read, but on much firmer ground in seeking to shed light on rationality than on curiosity.
Whether Letby is granted an appeal or not, whether she is found innocent or guilty at the appeal, the outcome will still be discounted by people who fervently believe the opposite.
I respectfully disagree. I agree with Sal Dyer’s comments above, and assumed she was guilty based on the evidence at trial and the findings of the judge and jury. If an appeal is granted, and evidence is presented to the contrary that deems her innocent, I would not discount that verdict either. No rational person would.
I suggest for a good counterpoint to this article readers should check out Peter Hitchen’s one in the Spectator. Not sitting through the months an months of the trial, perhaps paradoxically, gives one a clearer sight of the matters in hand. The relentless, repetitive bleakness of the story the jury was presented with – in the presence of plenty of the deceased children’s families – damned her despite its many flaws and omissions. The jury weren’t convinced by ‘good evidence and reasoning’ in Hitchen’s view (with which I entirely concur) – it was the sheer mass of the narrative they were presented with.
To say that those questioning the conviction (as I certainly do) aren’t getting the ‘whole picture’ is why we can see the flaws.
https://www.spectator.co.uk/article/why-i-believe-lucy-letbys-trial-was-unfair/
I’ve no idea if she did it or not.
But the more I read about the evidence on which she was convicted, the more concerns I have that it all adds up to “beyond reasonable doubt”.
Given the severity of the matter, I don’t think it’s good enough to shrug off multiple ways in which the safety of her conviction has been questioned, not only by Internet “sleuths” but also by recognised experts in fields like statistics.
We don’t “need to know whether Letby is innocent or guilty”. We only need to know whether Letby is guilty beyond reasonable doubt or not. The uncertainty of her guilt is the only defence she – and anyone else – needs to prove in a fair and just legal system.
And she failed to establish reasonable doubt in two separate full trials with differnt juries
In fact, it is more correct to say that the prosecution succeeded, with some help from the media, of convincing the jury to accept their theory. The principle arguments (other than the statistics) for and against were complex, so it is quite possible that emotions held sway. In that regard, nothing had changed as well for the retrial on the charge for which no verdict had been reached first time.
Another article starting out from a false prospectus.
There are actually three possibilities, Dr. Stock.
Lucy Letby is guilty. Current situation.
Lucy Letby is innocent.
Lucy Letby is guilty, but the conviction is unsafe.
People are rightly questioning the integrity of the process and whether the conviction is safe. It is vital that the public have confidence in the judicial system. This work needs to be done whether Letby is actually innocent or guilty.
This is the same principle as with the Birmingham Six – we don’t know for certain that they were innocent. We do know for certain that there was insuffient evidence to safely convict.
From what I’ve seen, serious legal professionals, statisticians and politicians are asking the right questions for the right reasons. And without any assumption about whether Lucy Letby is actually guilty or not. And I fully support what they are doing.
Since in the rest of your post, you seem to be saying exactly what I’m saying, I’m not sure what your first sentence is doing here.
It’s Kathleen btw.
She’s a PhD and professor. But more correctly Prof. Stock. My apologies to the Prof then.
Didn’t realise I needed your permission to comment !
And if you have a substantive comment beyond these two in this thread, it’s certainly not showing right now and I haven’t seen it. I know comments suddenly disappear for hours round here sometimes …
The first sentence is simply saying that starting out articles in this misleading way is very poor. I struggle to read past stuff like this – first impressions really do matter. Yet again, where are the editors and reviewers ?
Sorry, hadn’t realised you are actually Kathleen Stock ! Not quite sure how I’m supposed to guess that.
I wrote a short comment here which I would have deleted, except that there is no facility for doing that.
“Edit” then use the “Delete” or “Backspace” (sometimes just a long Left Arrow)
Thanks for writing this excellent article, Kathleen, and for posting here. I’m sure this is greatly appreciated by nearly all of us.
Prof. Stock, I think the problem with the article is that it asks the philosophical questions “What is (certain) truth?” Whereas many commenters, myself included, are adressing the mathematical questions “What possible truths are there and what is the probability of each?” Both are relevant to the application of the law.
Thank you Kathleen for an excellent article. Not living in Britain it has been easy to avoid reading about these cases and the trial until I saw your article. It is such a distressing occurrence, the deaths, the trial and the after-discussion. I have an aversion to cruelty to to children. It has enabled me to get up to date with the original and present issues. What do I think. I don’t know. It is all very disturbing.
Oh, he is only being polite
This point cannot be made enough. Too many people are turning this into a false dilemma.
edit – bullet points don’t work
>>>>>
Absolutely and thanks for saving me from having to post to point out this obvious failure in Stock’s article.
Agree there are far more than 2 possibilities, but since there are 7 deaths you must must multiply the above by 7, resulting in 21 possibilities. There is also – in each case – the possibility of harm without murder, such as negligence (by Letby or others or a combination of both). The binary presented by Prof. Stock excludes a range of possibilities. I list 15 in my other post.
However, as noted by others, the issue that the public should be very interested in is whether – and how much – bad evidence is used in the courts, particularly around the use of statistics.
Exactly. I read your comment on the range of outcomes this morning. A wonderfully clear explanation. It is clearly far more complex than a binary either/or.
There were actually more deaths again, but she was only convicted of 7
IIRC it was WS Church who said “There are Lies, Damned Lies and Statistics.
Disraeli?
For most epistemological knowledge we’re dealing with likelihoods, not truths (which is part of English law with the idea of ‘beyond reasonable doubt’).
Likelihoods can shift as new data, new ideas, new thoughts become apparent. Free speech is one way in which new viewpoints arise to update our likelihoods.
The Letby case seems impossible to judge from the outside. The known fact is that babies died, which is tragic, but the crux of the case seems to be mostly based on expert opinion and indirect evidence – ie expert likelihoods. Yet, the statistical evidence is complex, the medical evidence is complex and additional experts are coming in with different interpretations of the same data. From outside it’s impossible to say what the likelihood of innocence or guilt really is.
People have always had an unhealthy preoccupation with their fellow citizens guilt:
“The scribes and the Pharisees brought a woman who had been caught in adultery, and placing her in the midst they said to him, “Teacher, this woman has been caught in the act of adultery. Now in the Law, Moses commanded us to stone such women. So what do you say?” This they said to test him, that they might have some charge to bring against him. Jesus bent down and wrote with his finger on the ground. And as they continued to ask him, he stood up and said to them, “Let him who is without sin among you be the first to throw a stone at her.” And once more he bent down and wrote on the ground. But when they heard it, they went away one by one, beginning with the older ones, and Jesus was left alone with the woman standing before him. Jesus stood up and said to her, “Woman, where are they? Has no one condemned you?” She said, “No one, Lord.” And Jesus said, “Neither do I condemn you; go, and from now on sin no more.”]]”
His solemn reminder is always relevant:
“Judge not, that you be not judged. For with the judgment you pronounce you will be judged, and with the measure you use it will be measured to you. “
And what exactly was Jesus writing on the ground?
Why include that particular action? It smacks so insistently of the eyewitness. Or does it hold a deeper meaning? The finger, the stone, the dust, the law, the spirit, all these have hugely symbolic Biblical meanings.
One of the great and awesome mysteries of Scripture
When I click an article it doesn’t load. I then click on the address bar, press return and it then loads. This is an issue on every article. Sort it out Unherd.
The other angle to all this is that we have seen multiple recent examples of ‘the powers that be’ being perfectly willing to throw innocent people under the bus to mask their own inadequacies. There is a general feeling that the NHS would rather crush whistleblowers than take their concerns seriously. Like many people commenting here, I don’t know if she is guilty or innocent, but having a sense that cover-ups are the norm, and this might be one, can only add to the feeling of uncertainty in this case.
It’s rather the other way in this case, isn’t it? The NHS local management refused to take the concerns of Ms Letby’s colleagues seriously for a long time; like you I’m not saying anything about the unsafeness or otherwise of the conviction, but management should have investigated much earlier.
Agreed, this is what the public inquiry should be looking into, but of course it won’t. The Post Office might behave in this way but our beloved NHS? No, that is too awful to contemplate.
Sadly I’ve come to the same conclusion. The multiple examples of NHS failure and cover-up, especially with regard to maternity care in various locations but also not forgetting the blood transfusion scandal and the Covid injections. I’m heartbroken that so many choose to forget the institutional failures, corruption and suffering it has caused ordinary unsuspecting people. I’m very cautious now about any mainstream medical practitioners and hospital staff not because I don’t think they mean well but because I don’t trust their judgement.
In the American case, the nurse murdered a range of patients with insulin across multiple hospitals. All those hospitals covered up the crimes until a police investigation proved sufficiently tenacious in collaboration with a whistleblower.
KS writes an article about how everyone is dead set on their own opinion about the Letby case and just look at the comments section.
I don’t think I’ve ever seen such an outbreak of equanimity and reasonableness BTL on this site.
We’re a capricious lot, it would appear.
Perhaps the professor would care to deliver lectures on other contentious subjects
You do not have to be able to speak or understand English to sit on a British jury. I sat on a jury where 2 people did not speak English and they were the only people to say guilty. It was the only word they knew. This is quite intentional and has been the policy since 2009 – look it up.
I am not suggesting that you are making that up, but I do find that (even in the currently absurd state of affairs we live) rather hard to believe. An argument from incredulity, I know.
I have been quite credibly informed of a jury where competent speakers of English were in the minority.
I am suggesting she’s making it up. No judge or barrister is going to allow a jury member who can’t speak a word of English
I agree. It would be grounds to claim a mistrial that would be very hard to argue with, and judges never knowingly risk the damage to their reputation this involves.
Perhaps someone should have taught them the word ‘not’.
That rather reminds me of a telephone consultation with a GP locum a few years ago. Intelligent communication between us was such hard going that I gave up, said all was fine, put the ‘phone down, and crossed my fingers.
In what way is it intentional? Why?
The problem in this case is doubt not certainty. It’s all circumstantial. There’s not even conclusive proof that any of the deaths were from un-natural causes.
Indeed, in the light of which the failure to establish motive gives grave cause for concern.
Whether Letby is guilty or innocent, this and recent cases, the Post Office, Oliver Campbell etc show the legal system, particularly the appeal procedure, is more designed to massage lawyers ego and belief in their infallibity, than establish guilt or innocence.
But she was convicted on the basis that there was no reasonable doubt regarding her guilt. If there is uncertainty, she should be released.
But she wasn’t convicted on every count, on many cases the jury decided there wasn’t enough evidence to convict her which implies they listened carefully to the evidence provided in each case rather than being blinded by statistics
Let me guess ,that the same people who are saying “Free Lucy Letby” are the same crowd who are screaming “From the River to the Sea”
This article is incorrect (unusually for Prof. Stock) to assert that the only options are that Letby is guilty or innocent of everything she has been convicted of (although this may be how some journalists are presenting the story).
This would be the case if there had only been one death (although even in that case there is nuance – for example a fight outside a pub resulting in a death could be GBH, manslaughter or murder depending on what facts are established).
The possibilities are:
1. Letby guilty of 7 counts of murder;
2-7. Letby guilty of 6/5/4/3/2/1 counts of murder and 1/2/3/4/5/6 babies dued due to natural causes.
8-13. Letby guilty of 6/5/4/3/2/1 counts of murder and 1/2/3/4/5/6 babies dued due to preventable causes or negligence by Letby or the hospital management or a combination of both.
14. Letby innocent of murder, all the babies died due to negligence by Letby and/or the hospital management.
15. Letby innocent, all the babies died due to unpreventable natural causes.
As I have posted previously, what matters is that justice is done for the families not just Letby.
The reason this case is of public interest is because since the conclusion of the first trial, it has been clear that the evidence was based on a flawed use of statistics.
The same bad use of evidence occurred in the cases between the Post Office and sub-postmasters.
It is quite reasonable to have strong opinions about the operation of the British justice system (and arguably it is our civic duty to keep an eye on and protest this sort of thing) without engaging in conspiracy theories or having any view on which of possibilities 1-15 above may be correct.
Just to remark that (all other things being equal) the probability that LL is guilty of (eg.) 7 counts of murder is much lower than the conditional probability that she is guilty of 7 counts of murder given that she is guilty of one or more counts. So the 7 counts are not independent events, in the sense of probability theory.
True, but the problem with Bayesian probabilities is that by acknowledging that pre-conditions affect probabilities, which is true of course, one cannot limit the number of pre-conditions that should be taken into account.
E.g.
Say the probability, per se, that a person is guilty of a murder which they had the means to carry out, is 50%.
Given that a person has committed murder before, the probability becomes higher.
Given that the person has committed murder 6 times before, the probability is very very high.
But:
If that the the deceased was sick and there is a (known) level of probability that he have died from natural causes, the probabilty of murder is now lower.
Given a sewage leak into the area inhabited by the deceased, increasing the probability of cross-infection, the probability of murder is once again lower, etc.
The number of possible pre-conditions that affect a probability are multitudinous, potentially infinite (although with decreasing importance as they get further away from the event) and unmeasurable.
I don’t know if she’s guilty or not. Even if she is innocent, she’s better off in jail being looked after as her life is ruined now anyway.
One thing that has never been mentioned is her poor parents.
They too have lost a child and unlike the parents whose babies sadly died, their child is hated by society the same society that has such feeling for the other parents who lost their children.
A good article, but longer than it needed to be. Some highly credible statisticians have analysed the statistical evidence that was a cornestone of the prosecution case and found to be evidently unsupported by the underlying data. This is a fact that I am able to verify (I have expertise in the field of statistics). I am fully justified therefore in stating with certainty that her appeal should be allowed to proceed to retest the evidence. I can also state with equal certainty that anyone who says that her appeal should not be allowed is wrong. These are not beliefs, they are facts. I have no idea whether she is guilty or not.
Gee, so many experts here on Unherd.
As it happens, in this area I am indeed that most hated of things: an expert. Sorry to disappoint you.
EX an unknown quantity, SPURT a drip under pressure.
“This is a fact that I am able to verify (I have expertise in the field of statistics).”
Have you considered that a line like this is not convincing. You haven’t shown us your verification, claiming to have expertise means nothing in a comment (I could say i’m a psychologist and it’s clear that you’re not well), and saying “evidently unsupported” is not a great argument.
I understand that the late Mike Lynch, who died tragically in his super yacht “Bayesian” had taken an interest in the case following his own acquittal. His fortune was based on Bayesian probability theory which I instinctively used during my work as a diagnostic radiologist. If the prior probability of a disease was high, then the level of evidence to make a diagnosis (the posterior probability) was fairly low for example a simple chest x-ray to diagnose lung cancer in a heavy smoker. However for much rarer diseases the level of diagnostic “proof” needed to be much higher.
The prior probability that Letby was a mass murderer was exceedingly low, consequently the quality of evidence to push the diagnostic threshold over “beyond reasonable doubt” needed to be very high. The question being asked, was it?
On the other hand the prior probability of Mike Lynch’s yacht sinking in 16 minutes was exceedingly low ……
Belief often requires that one jettisons any knowledge based on good evidence and sound reasoning. Take the case of the present conflagration in the Middle East. Many believe, quite contrary to known facts, that the Palestinians are terrorists and the zionists are not; and as such the zionists have a natural right to decimate the Palestinians if necessary with help from others. These beliefs are held for partisan reasons or for the purpose of cocking a snook at the wicked Muslims though not all Palestinians are Muslim. However, their beliefs are not based on evidence. There is readily producible evidence that shows that zionists are in fact the terrorists who have left a trail of acts of terrorism, directed against Palestinians and others, in their wake. It can thus be justifiably maintained that if one accepts that the zionists are indeed terrorists, then the Palestinians are not.
I think you’ve solved the problem, everyone else is wrong.
Everyone else is either not in possession of the facts or are blindly partisan.
https://www.haaretz.com/israel-news/2023-06-21/ty-article-magazine/.highlight/zionist-military-org-efforts-to-recruit-nazis-in-fight-against-the-british-are-revealed/00000188-d93a-d5fc-ab9d-db7ae0ea0000
Letby is understood to have carried out two work placements at the Liverpool Women’s Hospital between October and December 2012, and January and February 2015.
Richard Baker KC, representing nine families, said collapses in neonatal units involving “unusual” complications such as dislodgement of endotracheal tubes are “uncommon”.
An audit carried out by Liverpool Women’s Hospital recorded that whilst Lucy Letby was working there, dislodgement of endotracheal tubes occurred in 40% of shifts that she worked.
“It generally occurs in less than 1% of shifts,” he told the inquiry.
Food for thought, or just another set of fallacious statistics?
Also Hospital bosses failed to investigate allegations against Lucy Letby and tried to silence doctors, the lead consultant at the neonatal unit where she worked has told the BBC.
The hospital also delayed calling the police despite months of warnings that the nurse may have been killing babies.
The unit’s lead consultant Dr Stephen Brearey first raised concerns about Letby in October 2015.
No action was taken and she went on to attack five more babies, killing two.
If if the stats are reliable they’re still only showing correlation, not causation. It’s not hard to envisage how the correlation might be the result of something else. For instance, shifts tend to be set according to patterns: Letby might be on a shift pattern that’s also the same pattern for some other nurse half a day previously, and the consequences of failures by that other nurse only show up several hours later, while Letby is on shift.
I’m not saying that’s what happened, merely pointing out that there may well be a complex causal web here that the investigation failed to identify.
I have been a juror on two trials and having been a firm supporter of the British jury system, came away highly disillusioned. At one trial one juror shouted indignantly…but… “it is an offence, punishable with a fine or imprisonment, for a juror to tell anyone about any statements, opinions, arguments or votes made by any jury members …
So I can’t tell you what was said but this along with many other incidents, seriously challenged what had previously been my firmly held belief in the British Jury system. Now in some cases I would prefer the French system of three judges hearing the evidence to arrive at a verdict.
The question now: Did ANYONE kill those children?
What’s sinister, and arguably incriminates SOMEONE, is that the case of the American nurse was so well-publicised (Hollywood/Netflix film starring Jess Chastain) that the British version also involved insulin poisoning.
I agree with both this article and the couple of others previously printed in Unherd, in particular the one last month that focused upon the faulty interpretation of statistical information (might have been by Tom Chivers but don’t recall exactly).
Even without the questionable theory advanced by Dr Dewi Evans, it appears that Letby’s conviction relied upon faulty interpretation of statistics and we’re learning at this point how absurdly easy it is even for highly intelligent people to make serious errors when interpreting such information. I support a retrial for Lucy Letby not because I have any belief in either her guilt or innocence: what I believe is that the trial in which she was convicted failed to answer that question: we still do not know.
I am a qualified actuary. As such, I have a reasonable understanding of statistics, though I do not claim to be an expert.
Like most other commentators, I do not know whether or not Letby is guilty. (I have my own opinions, but they are worthless.) What I do think is that there is reason to doubt that the “beyond reasonable doubt” criterion has been met.
When this enquiry was first announced, I was delighted. But it seems that all it is going to do is investigate details of NHS procedure, make some no doubt worthy recommendations (which will be quietly ignored), and fail to make it any easier for whistleblowers to come forward.
Now, what we really need is an enquiry into the use of “expert witnesses” in criminal trials. Judges, and lawyers generally, do not understand statistics. How could they? Some of them are downright suspicious – there are lies, damned lies and statistics. Jurors, of course, are even less likely to understand the statistics, though they are often impressed by those large numbers (“This would only happen by chance once in 70,000,000 cases” – Sally Clark – or “You are more likely to win the lottery than for this to occur”). In Letby’s case the problem may have been with the defence team, who just did not realise that these views could be challenged. Why would they? They are lawyers, not statisticians.
I have no doubt that similar problems arise with expert witnesses in medicine, engineering, physics and a multitude of other subjects. They have developed so much that the age of the generalist is long past. So the law needs to codify procedure. If that means neutral witnesses nominated by their profession and at public expense, so be it. Much better than miscarriages of justice.
That is not the use to which the statistics were put in Letby’s case though. In the Clark case, statistics were (mis)used to assert that there had been homicide. In Letby’s case, the statistics were used to show – as just one part of a circumstantial case – the unlikelihood of all these babies having issues befall them just when Letby happened to be on duty.
Dr. Stock, you are a consistently wise and thoughtful writer. But here, I am perplexed by your conclusion that “…it seems that this standard (of justifying your true beliefs with good evidence and reasoning) has not yet been collectively reached.” Firstly, why the concern with collectively? I did not put her on trial (from my couch in New England). The body that was directly concerned convicted her (unanimously) and her subsequent appeals were denied. Secondly, what standard are we aiming for? There is no absolute certainty in life. The evidence against Letby is damning, even if predominantly circumstantial. Let the court see evidence that would engender a reasonable doubt before we head down this path.
Lucy Letby. Are children still dying in that hospital and at what rate? How many died before she came on the scene? How many died when she was off duty? What about other hospitals with high infant mortality rates – is someone like her guilty of all the deaths or is it incompetence and carelessness by other hospital staff employed by their respective trusts? As for the supposed expert and air being pumped into blood vessels, is he interested in getting to the truth or worried about his reputation in the field (the ego that won’t back down, rather than the conscience that has doubt).
Did the doctor who claimed that he was suspicious of her, write it up in his notes or discuss it with colleagues who can remember the conversation, if not it is retrospective hearsay not evidence as no independent corroboration available. Also people lie, which is why you have written records (motive behind actions).
As for the notes where she admitted to feeling guilty about the infant deaths; did she state in any of them that she deliberately killed them or is it that she felt her incompetence killed them (over zealous conscience / naivety)?
Only one person knows if she’s guilty – herself. Everyone else is a spectator at the gallows or a knitter at the guillotine, indulging in gossip
Brilliant piece. Articulated the terrible dilemma so clearly.