Lucy Letby’s lawyers have said they will be asking the Court of Appeal to immediately review all of her convictions because an expert witness “has now changed his mind on the cause of death of three babies”.

The former nurse is serving 15 whole-life jail terms for murdering seven babies and trying to kill seven others while working as a neo-natal nurse at the Countess of Chester Hospital.

Her barrister Mark McDonald told a news conference in London that the lead prosecution expert, Dr Dewi Evans, had allegedly altered his view about how the babies died.

He said: “Remarkably, Dr Evans has now changed his mind on the cause of death of three of the babies: Baby C, Baby I and Baby P.”

The BBC has been unable to verify Mr McDonald’s statement.

Letby was convicted in August 2023 and has twice previously been refused permission to appeal against her convictions.

Speaking at London’s Royal Society of Medicine, Mr McDonald said: “The primary grounds of appeal at the previous hearings related to the admissibility before the jury of the evidence of the lead prosecution expert Dr Dewi Evans.

“The defence argued twice at trial that Dr Evans’ evidence should be disregarded. This was refused by the trial judge.

“It was then later argued in the Court of Appeal, and was refused in the court of appeal.”

The barrister added: “Dr Evans had said to the jury that Lucy Letby had injected air down a nasal gastric tube and this had led to the death of the three babies.

“This was repeated to the Court of Appeal, who may have been misled when they ruled on the application for leave against the convictions.”

He said Dr Evans had “revised his opinion in relation to Baby C” and had written a new report which he had given to police months ago.

But, he said “despite numerous requests” the prosecution had “yet to give this report to the defence”.

“The defence will argue that Dr Evans is not a reliable expert, and all the convictions are not safe,” Mr McDonald said.

Mr McDonald said he also had reports from two neonatologists that he claims count as fresh evidence in the cases of Baby C and Baby O, with no evidence of deliberate harm.

The nurse, 34, originally from Hereford, was convicted of the murders and attempted murders while working at the hospital between 2015 and 2016.

She made two attempts to kill one of her victims.

The Thirlwall Inquiry into how Letby was able to commit her crimes has been hearing evidence at Liverpool Town Hall since September.

It will resume in January, with findings expected to be published in autumn 2025.

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