As Lucy Letby becomes the most prolific serial child killer in modern Britain, we take a look at how she managed to slip under the radar for so long, carrying out her attacks unchallenged for a year at the Countess of Chester Hospital.
Gamal Fahnbulleh joins Mel Barham and Emma Sweeney on the latest episode of From the North.
As a little girl, Lucy Letby was the picture of innocence - she was an only child and grew up in the cathedral city of Hereford.
She said the dream of becoming a nurse took hold during her secondary school years.
Letby dedicated herself to her studies and graduated from the University of Chester in 2011.
After securing a job at the Countess of Chester Hospital in January 2012, she became known as a hard worker and even helped co-workers on hospital fundraisers as they campaigned for a new neonatal unit.
But prosecutors said behind the smiles was a 'calculating killer', a nurse on a year-long campaign of violence.
She has been found guilty of murdering seven babies who were being looked after in a neo-natal ward - making her the UK's most prolific killer of babies in modern times.
Letby has also been found guilty of attempting to murder a further six babies.
In 2015, the neonatal ward at the Countess of Chester was operating as a Tier 2 unit, providing short-term intensive care for sick and premature babies born between 27 and 32 weeks.
In June 2015, three babies died unexpectedly within two weeks of each other and another suffered a sudden collapse.
It would mark the start of a 12-month period, which in total, would see seven sudden deaths and a further 10 near fatalities.
Video report by Granada Reports' journalist, Emma Sweeney
Just weeks after the first events began to occur - an internal review was carried out.
Dr John Gibbs, a paediatric consultant from the unit, said concern had been raised about the unusual deaths - but no one believed anyone was harming babies.
He said: “As a result of those initial cases, concern was raised that they seemed unusual and that Lucy Letby was associated with those.
"But as far as I know, no other action was taken at that time.
"But to be fair, we consultant paediatricians and I didn’t really start to get very concerned that harm might be happening until into 2016."
By February 2016 - more babies had died and collapsed unexpectedly. An external review took place which was referred up to senior managers.
Dr Ravi Jayaram, another Consultant Paediatrician on the ward said: "I’ve been a paediatrician since 1992 and I had never, in my career seen, anything like this - never, ever.
"Not just the numbers but how they were dying - it did not make sense."
During the trial, the prosecution would say it was down to Lucy Letby, who had morphed into a 'constant malevolent presence'.
The nurse admitted she was often present, but on a unit that was increasingly short-staffed, she was the one willing to pick up the slack.
It was no secret the unit was struggling with staffing levels, and in February 2016, inspectors raised concerns with hospital bosses.
Their report said that whilst they could find "no definitive explanation for an increase in mortality rates" they had identified "significant gaps in medical and nursing rotas, poor decision-making and insufficient senior cover".
Michelle Warden was a former advanced neonatal nurse practitioner at the hospital before being made redundant in 2006.
She has friends who worked alongside Lucy Letby and told ITV Granada Reports: “They all say the same thing - that the unit was short-staffed.
"They had junior staff, inexperienced staff…There were no advanced neonatal nurse practitioners, there was no neonatologist.
"It was poorly staffed and staffed by inexperienced staff.”
Michelle Warden speaking about the staffing levels on the neonatal unit at the hospital
A jury found none of these issues was to blame. It was Lucy Letby, who the consultants say had been on the radar of senior executives, including the Medical Director and Director of Nursing as early as February 2016.
Dr Brearey - who was the head of the unit at the time - says he asked the senior managers for an urgent meeting that month, but it would take another 3 months for that meeting to take place.
Ian Harvey was the Medical Director at the time and says he does not recall "any such communication" in February 2016.
He went onto say: "It is surprising, given the level of concern that some of thepaediatricians professed having had at the time, that there was no follow up to chase a response, either with my secretary, or directly with me.
"As Medical Director I had an open door policy; if I was in my office and there wasn’t a meeting my door was open and anyone was able to call, be it with a professional or personal problem - as many did.
"At no time prior to May 2016 did a consultant paediatrician come to my office to express or discuss their concerns.
"Several of the criticisms you have shared are similar to those submitted in a complaint about me to the General Medical Council (GMC) in July 2018, by four consultant paediatricians at the Countess of Chester Hospital.
"Given the circumstances, there can be no doubt that the GMC conducted a thorough investigation. On the 3rd of May 2022, the GMC informed me that they had concluded their investigation and that the case was closed with no further action."
Dr Gibbs says consultants were told their claims about Lucy Letby were 'impossible' and 'inconceivable'
During her trial, Letby was painted as a nurse who calmly stood over babies as she sabotaged them and it was revealed that she cooked the records to give herself an alibi as the number of victims steadily rose.
Her defence said the case against her was built on a presumption of guilty - and in court, Letby insisted she was a dedicated, caring and conscientious nurse.
They insisted her only crime was falling victim to a gang of four consultants - who had conspired against her to cover up hospital failings.
"It felt uncomfortable [to be accused of conspiracy]," Dr Gibbs said. "But it was not surprising, it was a reasonable defence to take when you're accused of multiple murders and attempted murders.
"Lucy Letby was wrong, it wasn’t a gang of four, it was seven - all the consultant paediatricians not just four of us.
"It’s normal to review your practice and when you have an increased number of deaths to discuss them together - it was the deaths and the unusual nature of deaths that worried us, and then the fact that Lucy Letby had been involved in all of them was a big concern."
Despite those concerns, it was not until June of 2016, a year after the alarms were first sounded, that things finally came to a head.
Named by the prosecution as the 'tipping point', Letby had returned from a holiday in Ibiza to naturally conceived identical triplets on the unit, who were a healthy weight and were due to go home.
Letby killed two of the boys, Babies O and P, within 24 hours of each other.
The parents begged doctors to take their surviving triplet to another hospital, where a paediatrician agreed - believing the boy was in ‘mortal danger’. The baby boy was moved and survived.
But, by this point, Letby was responsible for murdering a total of seven babies and attempting to murder more.
The following month, in July, a meeting was held between hospital managers and some of the consultants.
“The very first thing that Tony Chambers - the Chief Executive - said to us, he cogitated for a few seconds and he said: ‘Well I can see how that might be a very convenient explanation for things'", Dr Jarayam said.
"Now let’s take a moment to think about that.
"We’ve just said to the Chief Executive of the hospital that we as a group of seven consultant paediatricians have got a serious concern that somebody could be causing deliberate harm to babies on our neonatal unit, and he tells us that he thinks that could be a convenient explanation for us.
"What that says to me is that he’d already decided that wasn’t going on and this was us just trying to cover up."
In response, Tony Chambers has said Dr Jayaram's account is "one-sided and what he said was "taken out of context."
Mr Chambers went onto say: "The implication, if any, was that a significant number of factors needed to be considered, including demand, acuity, clinical care, staffing andenvironment.
"In February 2016 there was a comprehensive CQC inspection at the hospital, including paediatrics and neonates. I am not aware that the consultants escalated any concerns with the CQC inspection team; nothing was reported to me at the time, or in any post-inspection feedback or report."
The former Chief Executive added: “All my thoughts are with the children at the heart of this case and their families and loved ones at this incredibly difficult time. I am truly sorry for what all the families have gone through.
“The crimes that have been committed are appalling and I am deeply saddened by what has come to light.
“The trial, and the lengthy police investigation, have shown the complex nature of the issues raised. I will co-operate fully and openly with any post-trial inquiry.”
Letby was removed from the unit, but it was more than two years before police finally charged her, in November 2020.
Operation Hummingbird was set up by Cheshire Police to investigate the deaths and collapses and became one of the biggest and most complex cases ever undertaken by the force.
An initial team of eight quickly increased, and at the height of the investigation, almost 70 officers and civilian staff were working on it.
The team gathered 32,000 pages of evidence and spoke to around 2,000 people, of which 250 were identified as potential witnesses.
During searches of Letby's home police found handwritten notes, with one post-it note reading: "I killed them on purpose... I am a horrible evil person".
Another included the statement: "I don't know if I killed them. Maybe I did. Maybe this is down to me".
Dr Gibbs says he believes senior management at the hospital has questions to answer.
“I think they need to be asked and they need to justify their decisions," Dr Gibbs said.
"I know what we paediatricians were concerned about and those concerns were being fed through to the senior managers.
"The people who’ve been affected most have been the poor parents involved. To have lost their babies in the neonatal unit is a tragedy, it’s devastating for them.
"To then find out that after a while, we were not sure why their babies might have died and then that we were suspicious it might have been deliberate harm - murder for some of the babies, attempted murder for others - and to go through a long police investigation, leading to a prolonged court case, has been just agony for the families."
He added: "I’m sorry that everything that’s happened has taken time to be resolved. I only hope that we've found the truth at the end of this."
What next for Letby?
Lucy Letby faces a lifetime behind bars. She will be sentenced on Monday 21 August.
Cheshire Police say the Operation Hummingbird team is "committed to a complete and thorough investigation into the full period of time that Lucy Letby was employed as a nurse, either while at the Countess of Chester Hospital or on placement at the Liverpool Women’s Hospital."
It continued: "The families of all babies, who are part of this investigation, have been informed and are supported.
"We will of course provide a more detailed update when we can.”
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