A leaked copy of Dr Hawdon’s report – which was never seen by the jury in the original trial – revealed she believed 13 of the 17 deaths and crashes could be explained.

The consultant made several recommendations, including that out-of-hours consultant attendance should be reviewed and that staff should be given extra help with intubating babies and giving antibiotics on time.

In four cases – Baby A, Baby I, Baby O and Baby P – the consultant deemed the deaths unexplained and said there should be a forensic examination.

Letby was convicted of killing all four babies, and the prosecution argued there was a wealth of evidence showing she was responsible for the deaths and attacks of many other infants.

Dr Hawdon’s review was one of a number of internal and external investigations into deaths and collapses at the hospital, of which the jury was not informed.

“Claims that Miss Letby was scapegoated”

The Royal College of Paediatrics and Child Health (RCPCH) was invited to look into the deaths in 2016 but found nothing to link Letby to them. Instead, it identified problems within the facility, such as understaffing.

Giving evidence at the Thirlwall inquiry on Monday, Claire McLaughlan, a lay assessor for the RCPCH, said she believed the allegations against Letby were “not based on fact” and appeared to be his personal opinion. Dr Stephen Breareyward consultant.

In a statement read out at the hearing, she said: “In my opinion, this was a person’s personal view, feelings, interpretation of Miss Letby. It was not based on facts; was uncorroborated.

“Even now I wouldn’t consider his point of view objective or unbiased because he was too involved, too close to the situation and had a conflict of interest.”

Giving evidence, she added: “They gave us a mixed picture because in one breath they told us about their concerns and the allegations they were making, but in the next breath they were telling us what a good nurse she was.

“The circumstances in which I was given this information was that there were a lot of claims at the time that Miss Letby was being scapegoated.”

Ms McLaughlan also said the RCPCH team had been given a “false level of reassurance” about Letby’s involvement by the management team at the Countess of Chester Hospital.

“It was kind of thrown into the conversation as a ‘by the way,’ it wasn’t given any level of importance or credence,” she said. “It was given to us as … almost a break in relations.

“We knew the cases had gone through a coroner’s investigation … they had gone through network analysis, so I don’t think we were in a place at that point to think the unthinkable. No red flags were raised.”

Ms McLaughlan accepted the RCPCH team should have stopped the review after learning of concerns about Letby in case it affected a future police investigation.

She agreed the review was a “missed opportunity” to prevent further deaths.