Lucy Letby: Defence calls for miscarriage of justice investigation as medics give alternative causes of death

A panel of international medical experts has given alternative causes of death in several cases against child serial killer Lucy Letby.

It comes as her defence lawyers announced they have asked for her case to be investigated as a miscarriage of justice.

Letby, 35, the UK's most prolific child killer of modern times, is serving fifteen whole life terms in prison after she was convicted at Manchester Crown Court of murdering seven infants and attempting to murder seven others between June 2015 and June 2016.

Various methods were used to attack the babies while Letby worked as a nurse on the neonatal unit at the Countess of Chester Hospital.

One method was air being injected into the bloodstream which caused an air embolism, blocking the bloody supply and leading to sudden and unexpected collapses.

On Tuesday, retired neonatologist Dr Shoo Lee, who co-authored an academic paper on air embolisms (bubbles) in babies in 1989 which featured prominently during her trial, chaired a panel of 14 experts to compile an "impartial evidence-based report".

Dr Lee said he believed his findings on skin mottling were misinterpreted by the prosecution. He said in a new paper he published in December 2024 that there were no cases of skin discolouration when air was injected into the veins.

At her trial in 2023, prosecutors pointed to skin discolouration in several of the victims as evidence that air had been injected into their veins by Letby.

"The notion that these cases are air embolism because they collapsed and because there were skin rashes has no basis in evidence. Let's be clear about that," Dr Lee said.

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The panel laid out alternative causes of death in many of the cases, including natural causes and poor medical care at Countess of Chester Hospital.

"We did not find any murders," Dr Lee said. "In all cases, death or injury were due to natural causes or just bad medical care."

Asked about the Countess of Chester Hospital, Dr Lee, a retired medic from Canada, said: "I would say if this was a hospital in Canada, it would be shut down. It would not be happening."

A spokesperson at the Countess of Chester Hospital NHS Foundation Trust said: "Due to the Thirlwall Inquiry and the ongoing police investigations, it would not be appropriate to comment further at this time."

The Criminal Cases Review Commission (CCRC) will now review all the evidence after an application from the defence to determine if the case should be referred back to the courts.

A CCRC spokesperson said: "We are aware that there has been a great deal of speculation and commentary surrounding Lucy Letby's case, much of it from parties with only a partial view of the evidence.

"We ask that everyone remembers the families affected by events at the Countess of Chester Hospital between June 2015 and June 2016.

"We have received a preliminary application in relation to Ms Letby's case, and work has begun to assess the application."

Opening the press conference, MP Sir David Davis described Letby's convictions as "one of the major injustices of modern times".

Last year Letby lost two bids to challenge her convictions at the Court of Appeal - in May for seven murders and seven attempted murders, and in October for the attempted murder of a baby girl, which she was convicted of by a different jury at a retrial.

In December, the former nurse's barrister, Mark McDonald, said he would seek permission from the Court of Appeal to re-open her case on the grounds Dr Dewi Evans, the lead prosecution medical expert at her trial, was "not reliable".

Dr Evans, a retired consultant paediatrician, said concerns regarding his evidence were "unsubstantiated, unfounded, inaccurate".

In September a public inquiry into how Letby was able to commit her crimes began hearing evidence. Closing legal submissions are expected in March and the findings are expected to be published this autumn.

Detectives from Cheshire Constabulary are also continuing their review of the care of some 4,000 babies admitted to the Countess of Chester Hospital from January 2012 to the end of June 2016, while Letby worked as a neonatal nurse, there. It also includes two work placements at Liverpool Women's Hospital in 2012 and 2015.

Letby has been interviewed under caution at HMP Bronzefield in Ashford, Surrey, in relation to the ongoing investigation into baby deaths and non-fatal collapses.

She maintains her innocence.

(c) Sky News 2025: Lucy Letby: Defence calls for miscarriage of justice investigation as medics give alte