“even Letby admitted that somebody was killing children in the COCH hospital.”
This is not the full story.
She and her Defence team were told pre-trial that experts had confirmed that tests had proved 2 babies were deliberately poisoned with insulin. However, the tests used do not prove poisoning. Prof Vincent Marks who helped convict Allitt stated that using the tests alone without physical evidence such as contaminated equipment or additional analysis of the blood samples risked miscarriages of justice.
Prosecutor Johnson used Letby’s acceptance against her during her cross- examination, but it was based upon Letby being provided misleading and incomplete evidence!
“Why would Letby’s colleagues and the police try to frame her anyway?”
“Frame” is not what is being claimed
The consultants and lead expert convinced the Cheshire Police she was guilty early on and from that point the Police worked on the presumption of guilt and viewed all the information they obtained to support guilt. There is no doubt they think she is guilty, although their confidence will have been dented by the Child K Retrial.
For the consultants, because the alternative explanation is a combination of factors relating to prematurity, but also inadequate care at the Unit and the fact that Lucy Letby won a grievance after complaining about their treatment of her.
Like the Post Office it is a train that no one was able to stop.
I believe she was an escape goat. The doctors are responsible and the hospital for not to have proper equipment for very sick babies. When she left there were fewer deaths because the hospital was no longer allowed to care for the must vulnerable babies. The hospital was downgraded. One of the babies had to be transferred to a proper hospital and sometimes there were not even incubators for the babies. A total disgrace.
I believe she was an escape goat. The doctors are responsible and the hospital for not to have proper equipment for very sick babies. When she left there were fewer deaths because the hospital was no longer allowed to care for the must vulnerable babies. The hospital was downgraded. One of the babies had to be transferred to a proper hospital and sometimes there were not even incubators for the babies. A total disgrace.
“ Unless they are born with a serious health condition, they just need to be fed and kept warm and they will grow until they are big enough to be discharged”
The babies in this case were receiving life support ventilation in specialist cots to provide enough Oxygen to keep them alive. In one case it is possible attempts to withdraw ventilation may have lead to collapse.
Please research more widely than the Daily Mail Podcast, which was produced with the cooperation of Cheshire Police throughout the trial.
Rachel Aviv didn’t reduce the prosecution’s case to a single spreadsheet though. You’re arguing against a field full of straw men here. It’s also irresponsible to admit you don’t haven’t researched the case at all, and you couldn’t be bothered doing so, but nonetheless you will make a statement like “Is she innocent? Almost certainly not” from such a height of pompous, self satisfied, ignorance that you must have a nose bleed. Nobody asked you to opine on this. If you are too lazy to bother doing a modicum of research beyond passively slurping up a podcast from the Daily Mail’s trough, which by the way, could never have all of the evidence because it was limited to what was presented in court, and juries are never shown all the evidence. This is an ignorant and unnecessary piece. Actually do some work or just don’t bother. You have contributed precisely nothing to this conversation.
Due diligence is doing adequate research first and the fact the author of this article openly state you haven't indicates you are negligent to a point of absurdity.
I’m not going to read 7,000 pages of transcripts and I bet you aren’t either. The people who did the most due diligence were on the jury and they concluded that she’s guilty.
Basing your opinion on the work of two journalists, who also have a podcast and need listeners, is rather weak. These reporters have no medical background and thus cannot separate the wheat from the chaff. They can only report on what they have heard, or better, what they have been told.
Reading UK newspaper articles I was shocked how little critical thinking I found. No reporter asking: could there be another explanation ? Or maybe, if they tried, they were kept back by their editor. The "evil serial killer nurse" was a great seller.
An excellent and articulate diatribe against Snowdon who is just one of many who feel it necessary to opine on this case and do so without any expertise. Thank you (not) Christopher Snowdon for your contribution.
“ Instead, the staff at the COCH observed an extraordinary number of unexplained deaths and collapses and became increasingly suspicious of Letby.”
This is a fundamental misunderstanding of the case. The deaths were explained at the time. They had coroner reports and autopsies which concluded natural cause of death. Doctors at the time also believed the deaths were natural.
The unexplained label was slapped on later after Dr Evans starting going through cases.
Deaths were happening on that ward. Everyone and everything should have been investigated. Instead the police zoomed in on Lucy Letby - based on gut-feelings. They allowed the two Consultants who, based on their presence on the ward should have been suspects too, to rummage through the files looking for evidence.
In this retrial Dr Ravi (who is already a semi-famous tv personality, working with ITV on the Letby story to be produced by Netflix) admitted a trainee dr under his supervision had to make 3 attempts to insert the naso gastric tube in question.
I have no idea if Dr Ravi was motivated to lie to protect his own ambition and reputation, but certainly a conflict of interest should be considered. It should also be obvious that multiple collapses and deaths do not reflect well on senior drs. The unit was downgraded for many reasons including the availability of senior drs, after an investigation and official report - which was scathing.
The evidence against Lucy Letby is questionable. As another reader pointed out the insulin test was not definitve - the lab report stated a further test was needed - that was not done. The x-ray specialist at Great Ormond St looking for evidence of air embolism in two babies, found no indication in one and a small amount in the second. He stated that could have been caused by the three attempts made earlier to insert a tube into the baby's stomach button.
There are many such doubts on the science. Read the statements from the trial.
A final point - Cheshire police auctioned off the Letby story to the highest bidder -which was ITV. They are working with ITV. Is this reasonable or normal?
> A final point - Cheshire police auctioned off the Letby story to the highest bidder -which was ITV. They are working with ITV. Is this reasonable or normal?
That's scummy. But it's not really evidence either way as to Letby's guilt or innocence.
"There were only three early neonatal deaths a year at the COCH in the two years before Letby was working in intensive care at the hospital. In 2015, there were 8 (including 3 in June alone) and in 2016 there were 7. After Letby was suspended, the annual rate dropped to two." - Christopher S. Yet "The Countess of Chester, which looks after about 400 babies a year, stopped providing care for babies born earlier than 32 weeks in July last year." i.e. extreme preterm and very preterm babies (due to a number of failings in the hospital) BBC, 8 Feb 2017 https://www.bbc.com/news/uk-england-merseyside-38901317. Changes happened around the same time as her removal. The numbers are small, and it is a comparison of two years vs another two years, which means more care should be taken with the analysis. That's just from a cursory read of the story so should serve as a health warning.
You’re a consultant who suspects a woman is murdering babies but you’re content to finish your shift and leave vulnerable babies in her care. Over and over again. Make it make sense. My experiences of the NHS personally and of my mother working in it ensures I KNOW she is innocent. The consultants are cunts.
“The conspiracy theory is that problems with the sewage system at the hospital caused a wave of infections that was responsible for the deaths and that NHS management threw Letby under the bus to avoid a scandal.”
The sceptics I’ve read, and Snowdon’s cited here, have centred on the motives of the consultants heading up the failing unit, not the management.
In making a case, it’s best to present the opposing argument, not obscure it.
"the unusual rise in the number of deaths at the COCH"
FYI the variation wasn't particularly unusual, either compared to in other hospitals or, as the New Yorker pointed out, compared to other departments in the same hospital.
The thing that gets me is that there are a large number of healthcare professionals, and a lot of different ways they can look guilty. In every given time period one professional is going to look the most guilty, and given the numbers they are likely to look very guilty indeed. This is quite different from most murder trials where it is extremely likely that a murder has occurred, and you can exclude a large number of innocent possibilities. But the investigation and trial don't seem to have properly taken this into account.
Similarly, we know from Dr Evan's review of suspicious incidents that he has an extremely high false positive rate. It seems to be their ability to connect the cases he highlighted to Letby, however weakly, rather than anything in the cases themselves, that results in prosecutions.
Premature babies do, in fact, die all the time. The death rate for the first day of life is so high it won't be until your 80s you'll be at such great risk again… and that's including full term babies!
None of the methods of murder make any sense. One said “overfeeding” because a baby spit up. Have they ever met a baby? They spit up massive amounts, constantly, and premature babies even more, because of an immature oesophagaeal spincter.
Anyone cause of death to be overfeeding because of the quantity of spit up is full of shit. Did they measure the amount of spit up? No.
There's plenty of reasonable doubt to be had, and that's the standard of evidence.
Oh dear, a denier of the probability that Lucy Letby has been a convenient scapegoat for a failing unit.
There's not a single witness of LL doing anything and comments like "oh no, not lovely Lucy" makes one realise they'd found their cover-up victim. Not a shred of evidence, even that fine TV doctor said he caught her red handed doing nothing, as nothing was attempted murder. Swipe data shows she'd swiped out of the unit, not in. She couldn't remember the incident because she wasn't there.
Nurses have explained that babies, also premature ones, can dislodge a breathing tube. They also said that often if that happens they wait a few minutes to see if the baby can manage to get into the breathing rhythm by themselves. Preferable over yet another procedure, causing stress to the baby - which is not good. for them.
Does anyone else think it is utterly ludicrous to ask a group of 12 lay people to evaluate complex scientific information with zero scientific training and expect a reliable outcome? ( This is just as relevant regardless as to whether you think she is guilty or not guilty). Surely the system is utterly flawed in this respect. Wouldn't it have been a good idea to at least round up a jury of scientists with some relevant knowledge and training?
You make a good point - but I also feel a good defence lawyer should be able to break this down into layman's terms. The x- ray specialist at Great Ormond St found no evidence of air embolism in one baby (yet she was found guilty- method of murder undetermined ) and a small amount in the second which could have been due to 3 earlier attempts by drs to insert a tube through the child's naval button. Again she was found guilty. Either the defence failed to forcefully point this out, or the jury simply ignored it.
Did Letby explain why she wrote the pessimistic statements about never having a family of her own or a future? It sounds like a doomsday clock was ticking away in her head. It must be hard, waiting for that inevitable knock on the door!
Yes these scribbles followed multiple hours of police interrogations where she was accused of being somewhere between Genghis Khan and Vlad the impaler. She doubted her own abilities and her sanity in writing these short texts, trying to make sense of police accusations against her.
The police found in Lucy's diary the letters LO which to them implied her intent to harm a baby that day. It turned out to be LD, letters commonly used by nurses to indicate a Long Day.
The difficulty here is that *something* very unusual definitely happened at the COCH. Either there was a very peculiar string of coincidences leading to an unusually large number of deaths; or there was a serial killer of premature babies on the loose. Both of these are extremely improbable. The difficulty is working out which is more improbable; this is *very* hard; we have a strong tendancy to round very unlikely things off as impossible (or be convinced that they are much more likely than they really are).
I am not aware of anyone ever, prior to this case, having serially murdered newborn babies. Serial killers are rare enough in the first place; also, they are overwhelmingly men, and generally target sexually desirable women. My generally feeling is that the probability of Lucy being a serial killer of babies is so astronomically low, that the improbable coincindence is in fact more likely, despite it being very unlikely. I am not at all confident in this, though; like I say, it's very hard to reason well about this kind of incident.
We do know as fact that the neonatal unit was downgraded - no longer allowed to take babies born more than 8 weeks early because it was deemed unfit to do so. Which is why the death rate dropped. A good question is how long was it able to take extremely premature babies. What time period.
As I understand it, the CoCH neonatal became a Level-2 unit in 2014, and that continued in 2015 and 2016. The unit went back to level-1 in 2017, after a review - requested by the hospita - was done by the Royal College of Pediatrics and Child Health.
I agree that it's difficult to reason about this kind of situation, and that our priors should account for the rarity of female serial killers more generally. But it doesn't seem exceptionally rare for women to kill infants.
There are a few established cases of this specific type of serial killer - Amelia Dyer, Beverly Allitt, Miyuki Ishikawa, Genene Jones - all were medical professionals who killed multiple infants. (If we're being generous with the definition, there could be 1000s of midwives in China who could technically be identified as serial killers, but that's obviously a different situation.)
As this case also reveals the challenges of identifying/prosecuting perpetrators - I guess there are many who were suspected, but have managed to get away with it.
Obviously not identical, but post-partum psychosis occurs in around 1 in 1000 mothers, and can leads to infanticide/neonaticide; from https://en.wikipedia.org/wiki/Infanticide:
"Parental infanticide researchers have found that mothers are more likely to commit infanticide.[2] In the special case of neonaticide (murder in the first 24 hours of life), mothers account for almost all the perpetrators. Fatherly cases of neonaticide are so rare that they are individually recorded.[3]"
I guess my sense is that this behaviour is an extreme manifestation of a not-exceptionally-uncommon, mainly female pathology. Perhaps it's also the case that many people are a little bit murder-curious, but very few of us are in a position to kill so easily and get away with it.
Thank you for drawing my attention to these other cases; this does materially raise my assessment of the probability that Lucy is guilty, quite a lot.
Amelia Dyer seems somewhat different, both in that she had actual practical motive for at least her early murders (relieve herself of a burden of care), and that she was quite clearly insane. Miyuki Ishikawa had a profit motive. The other two are more direct parallels.
“even Letby admitted that somebody was killing children in the COCH hospital.”
This is not the full story.
She and her Defence team were told pre-trial that experts had confirmed that tests had proved 2 babies were deliberately poisoned with insulin. However, the tests used do not prove poisoning. Prof Vincent Marks who helped convict Allitt stated that using the tests alone without physical evidence such as contaminated equipment or additional analysis of the blood samples risked miscarriages of justice.
Prosecutor Johnson used Letby’s acceptance against her during her cross- examination, but it was based upon Letby being provided misleading and incomplete evidence!
She said no such thing.
“Why would Letby’s colleagues and the police try to frame her anyway?”
“Frame” is not what is being claimed
The consultants and lead expert convinced the Cheshire Police she was guilty early on and from that point the Police worked on the presumption of guilt and viewed all the information they obtained to support guilt. There is no doubt they think she is guilty, although their confidence will have been dented by the Child K Retrial.
For the consultants, because the alternative explanation is a combination of factors relating to prematurity, but also inadequate care at the Unit and the fact that Lucy Letby won a grievance after complaining about their treatment of her.
Like the Post Office it is a train that no one was able to stop.
I believe she was an escape goat. The doctors are responsible and the hospital for not to have proper equipment for very sick babies. When she left there were fewer deaths because the hospital was no longer allowed to care for the must vulnerable babies. The hospital was downgraded. One of the babies had to be transferred to a proper hospital and sometimes there were not even incubators for the babies. A total disgrace.
I believe she was an escape goat. The doctors are responsible and the hospital for not to have proper equipment for very sick babies. When she left there were fewer deaths because the hospital was no longer allowed to care for the must vulnerable babies. The hospital was downgraded. One of the babies had to be transferred to a proper hospital and sometimes there were not even incubators for the babies. A total disgrace.
Rare to see a genuine escape goat in the wild.
“ Unless they are born with a serious health condition, they just need to be fed and kept warm and they will grow until they are big enough to be discharged”
The babies in this case were receiving life support ventilation in specialist cots to provide enough Oxygen to keep them alive. In one case it is possible attempts to withdraw ventilation may have lead to collapse.
Please research more widely than the Daily Mail Podcast, which was produced with the cooperation of Cheshire Police throughout the trial.
Rachel Aviv didn’t reduce the prosecution’s case to a single spreadsheet though. You’re arguing against a field full of straw men here. It’s also irresponsible to admit you don’t haven’t researched the case at all, and you couldn’t be bothered doing so, but nonetheless you will make a statement like “Is she innocent? Almost certainly not” from such a height of pompous, self satisfied, ignorance that you must have a nose bleed. Nobody asked you to opine on this. If you are too lazy to bother doing a modicum of research beyond passively slurping up a podcast from the Daily Mail’s trough, which by the way, could never have all of the evidence because it was limited to what was presented in court, and juries are never shown all the evidence. This is an ignorant and unnecessary piece. Actually do some work or just don’t bother. You have contributed precisely nothing to this conversation.
Due diligence is doing adequate research first and the fact the author of this article openly state you haven't indicates you are negligent to a point of absurdity.
Absolutely. BTW, Snowdon just denied this then blocked me for saying as much on X.
Then, you count all the other issues he has ignored / is ignorant of, and...
I’m not going to read 7,000 pages of transcripts and I bet you aren’t either. The people who did the most due diligence were on the jury and they concluded that she’s guilty.
If you can’t be bothered to research the matter properly why comment at all?
What have you read that I haven't?
A shit load more
Like what? Some blog posts?
Basing your opinion on the work of two journalists, who also have a podcast and need listeners, is rather weak. These reporters have no medical background and thus cannot separate the wheat from the chaff. They can only report on what they have heard, or better, what they have been told.
Reading UK newspaper articles I was shocked how little critical thinking I found. No reporter asking: could there be another explanation ? Or maybe, if they tried, they were kept back by their editor. The "evil serial killer nurse" was a great seller.
Nice to have a juror commenting. So, what actually happened?
An excellent and articulate diatribe against Snowdon who is just one of many who feel it necessary to opine on this case and do so without any expertise. Thank you (not) Christopher Snowdon for your contribution.
“ Instead, the staff at the COCH observed an extraordinary number of unexplained deaths and collapses and became increasingly suspicious of Letby.”
This is a fundamental misunderstanding of the case. The deaths were explained at the time. They had coroner reports and autopsies which concluded natural cause of death. Doctors at the time also believed the deaths were natural.
The unexplained label was slapped on later after Dr Evans starting going through cases.
Exactly what happened to Lucia de Berk.
Deaths were happening on that ward. Everyone and everything should have been investigated. Instead the police zoomed in on Lucy Letby - based on gut-feelings. They allowed the two Consultants who, based on their presence on the ward should have been suspects too, to rummage through the files looking for evidence.
"Beyond reasonable doubt" is the key phrase here.
In this retrial Dr Ravi (who is already a semi-famous tv personality, working with ITV on the Letby story to be produced by Netflix) admitted a trainee dr under his supervision had to make 3 attempts to insert the naso gastric tube in question.
I have no idea if Dr Ravi was motivated to lie to protect his own ambition and reputation, but certainly a conflict of interest should be considered. It should also be obvious that multiple collapses and deaths do not reflect well on senior drs. The unit was downgraded for many reasons including the availability of senior drs, after an investigation and official report - which was scathing.
The evidence against Lucy Letby is questionable. As another reader pointed out the insulin test was not definitve - the lab report stated a further test was needed - that was not done. The x-ray specialist at Great Ormond St looking for evidence of air embolism in two babies, found no indication in one and a small amount in the second. He stated that could have been caused by the three attempts made earlier to insert a tube into the baby's stomach button.
There are many such doubts on the science. Read the statements from the trial.
A final point - Cheshire police auctioned off the Letby story to the highest bidder -which was ITV. They are working with ITV. Is this reasonable or normal?
> A final point - Cheshire police auctioned off the Letby story to the highest bidder -which was ITV. They are working with ITV. Is this reasonable or normal?
That's scummy. But it's not really evidence either way as to Letby's guilt or innocence.
No- but is there a conflict of interest there.
"There were only three early neonatal deaths a year at the COCH in the two years before Letby was working in intensive care at the hospital. In 2015, there were 8 (including 3 in June alone) and in 2016 there were 7. After Letby was suspended, the annual rate dropped to two." - Christopher S. Yet "The Countess of Chester, which looks after about 400 babies a year, stopped providing care for babies born earlier than 32 weeks in July last year." i.e. extreme preterm and very preterm babies (due to a number of failings in the hospital) BBC, 8 Feb 2017 https://www.bbc.com/news/uk-england-merseyside-38901317. Changes happened around the same time as her removal. The numbers are small, and it is a comparison of two years vs another two years, which means more care should be taken with the analysis. That's just from a cursory read of the story so should serve as a health warning.
Not true.
David, your other comments suggest you agree with what I've written. You should take more time with your responses or else read more carefully.
You’re a consultant who suspects a woman is murdering babies but you’re content to finish your shift and leave vulnerable babies in her care. Over and over again. Make it make sense. My experiences of the NHS personally and of my mother working in it ensures I KNOW she is innocent. The consultants are cunts.
Have you read any of the pieces on this substack https://lawhealthandtech.substack.com/
This is genuinely devastating. So upsetting to read all of the egregious errors and malpractice
“The conspiracy theory is that problems with the sewage system at the hospital caused a wave of infections that was responsible for the deaths and that NHS management threw Letby under the bus to avoid a scandal.”
The sceptics I’ve read, and Snowdon’s cited here, have centred on the motives of the consultants heading up the failing unit, not the management.
In making a case, it’s best to present the opposing argument, not obscure it.
So the consultants wanted something covered up? Explain to me how that worked?
"the unusual rise in the number of deaths at the COCH"
FYI the variation wasn't particularly unusual, either compared to in other hospitals or, as the New Yorker pointed out, compared to other departments in the same hospital.
The thing that gets me is that there are a large number of healthcare professionals, and a lot of different ways they can look guilty. In every given time period one professional is going to look the most guilty, and given the numbers they are likely to look very guilty indeed. This is quite different from most murder trials where it is extremely likely that a murder has occurred, and you can exclude a large number of innocent possibilities. But the investigation and trial don't seem to have properly taken this into account.
Similarly, we know from Dr Evan's review of suspicious incidents that he has an extremely high false positive rate. It seems to be their ability to connect the cases he highlighted to Letby, however weakly, rather than anything in the cases themselves, that results in prosecutions.
Premature babies do, in fact, die all the time. The death rate for the first day of life is so high it won't be until your 80s you'll be at such great risk again… and that's including full term babies!
None of the methods of murder make any sense. One said “overfeeding” because a baby spit up. Have they ever met a baby? They spit up massive amounts, constantly, and premature babies even more, because of an immature oesophagaeal spincter.
Anyone cause of death to be overfeeding because of the quantity of spit up is full of shit. Did they measure the amount of spit up? No.
There's plenty of reasonable doubt to be had, and that's the standard of evidence.
Oh dear, a denier of the probability that Lucy Letby has been a convenient scapegoat for a failing unit.
There's not a single witness of LL doing anything and comments like "oh no, not lovely Lucy" makes one realise they'd found their cover-up victim. Not a shred of evidence, even that fine TV doctor said he caught her red handed doing nothing, as nothing was attempted murder. Swipe data shows she'd swiped out of the unit, not in. She couldn't remember the incident because she wasn't there.
Nurses have explained that babies, also premature ones, can dislodge a breathing tube. They also said that often if that happens they wait a few minutes to see if the baby can manage to get into the breathing rhythm by themselves. Preferable over yet another procedure, causing stress to the baby - which is not good. for them.
Does anyone else think it is utterly ludicrous to ask a group of 12 lay people to evaluate complex scientific information with zero scientific training and expect a reliable outcome? ( This is just as relevant regardless as to whether you think she is guilty or not guilty). Surely the system is utterly flawed in this respect. Wouldn't it have been a good idea to at least round up a jury of scientists with some relevant knowledge and training?
You make a good point - but I also feel a good defence lawyer should be able to break this down into layman's terms. The x- ray specialist at Great Ormond St found no evidence of air embolism in one baby (yet she was found guilty- method of murder undetermined ) and a small amount in the second which could have been due to 3 earlier attempts by drs to insert a tube through the child's naval button. Again she was found guilty. Either the defence failed to forcefully point this out, or the jury simply ignored it.
Absolutely.
Did Letby explain why she wrote the pessimistic statements about never having a family of her own or a future? It sounds like a doomsday clock was ticking away in her head. It must be hard, waiting for that inevitable knock on the door!
Yes these scribbles followed multiple hours of police interrogations where she was accused of being somewhere between Genghis Khan and Vlad the impaler. She doubted her own abilities and her sanity in writing these short texts, trying to make sense of police accusations against her.
The police found in Lucy's diary the letters LO which to them implied her intent to harm a baby that day. It turned out to be LD, letters commonly used by nurses to indicate a Long Day.
The difficulty here is that *something* very unusual definitely happened at the COCH. Either there was a very peculiar string of coincidences leading to an unusually large number of deaths; or there was a serial killer of premature babies on the loose. Both of these are extremely improbable. The difficulty is working out which is more improbable; this is *very* hard; we have a strong tendancy to round very unlikely things off as impossible (or be convinced that they are much more likely than they really are).
I am not aware of anyone ever, prior to this case, having serially murdered newborn babies. Serial killers are rare enough in the first place; also, they are overwhelmingly men, and generally target sexually desirable women. My generally feeling is that the probability of Lucy being a serial killer of babies is so astronomically low, that the improbable coincindence is in fact more likely, despite it being very unlikely. I am not at all confident in this, though; like I say, it's very hard to reason well about this kind of incident.
We do know as fact that the neonatal unit was downgraded - no longer allowed to take babies born more than 8 weeks early because it was deemed unfit to do so. Which is why the death rate dropped. A good question is how long was it able to take extremely premature babies. What time period.
As I understand it, the CoCH neonatal became a Level-2 unit in 2014, and that continued in 2015 and 2016. The unit went back to level-1 in 2017, after a review - requested by the hospita - was done by the Royal College of Pediatrics and Child Health.
I agree that it's difficult to reason about this kind of situation, and that our priors should account for the rarity of female serial killers more generally. But it doesn't seem exceptionally rare for women to kill infants.
There are a few established cases of this specific type of serial killer - Amelia Dyer, Beverly Allitt, Miyuki Ishikawa, Genene Jones - all were medical professionals who killed multiple infants. (If we're being generous with the definition, there could be 1000s of midwives in China who could technically be identified as serial killers, but that's obviously a different situation.)
As this case also reveals the challenges of identifying/prosecuting perpetrators - I guess there are many who were suspected, but have managed to get away with it.
Obviously not identical, but post-partum psychosis occurs in around 1 in 1000 mothers, and can leads to infanticide/neonaticide; from https://en.wikipedia.org/wiki/Infanticide:
"Parental infanticide researchers have found that mothers are more likely to commit infanticide.[2] In the special case of neonaticide (murder in the first 24 hours of life), mothers account for almost all the perpetrators. Fatherly cases of neonaticide are so rare that they are individually recorded.[3]"
I guess my sense is that this behaviour is an extreme manifestation of a not-exceptionally-uncommon, mainly female pathology. Perhaps it's also the case that many people are a little bit murder-curious, but very few of us are in a position to kill so easily and get away with it.
Thank you for drawing my attention to these other cases; this does materially raise my assessment of the probability that Lucy is guilty, quite a lot.
Amelia Dyer seems somewhat different, both in that she had actual practical motive for at least her early murders (relieve herself of a burden of care), and that she was quite clearly insane. Miyuki Ishikawa had a profit motive. The other two are more direct parallels.