Inquiry Into ‘Killer Nurse’ Won’t Weigh Key Question: Is She Innocent?

A public inquiry into the case of Lucy Letby, a British neonatal nurse convicted of killing seven babies, has come under fire from scientific and medical experts who have called for it to be delayed or broadened to consider whether the deaths could have been caused by other factors.

The inquiry, set to begin on Sept. 10, will cast a fresh spotlight on one of the most haunting murder cases in recent British history. Conscientious and well liked by her colleagues, Ms. Letby was found guilty of killing seven infants, and trying to kill seven others, in a busy public hospital in 2015 and 2016.

Ms. Letby, 34, was sentenced to life in prison last year and her requests for appeals have so far been denied. But questions about the handling of the investigation and the evidence used to convict her have grown harder to ignore, with prominent experts in statistics and neonatal medicine arguing that both were gravely flawed.

Under the terms of its mandate, the inquiry will not scrutinize those questions. Instead it will hold hearings to probe the experiences of the families of the babies who died and the conduct of nurses, doctors, and other health workers at the Countess of Chester Hospital, southeast of Liverpool.

Led by Kate Thirlwall, an appeals court justice, the inquiry aims to determine “whether suspicions should have been raised earlier, whether Lucy Letby should have been suspended earlier, and whether the police or other external bodies should have been informed sooner about suspicions about her.”

The thornier question — whether Ms. Letby might have been wrongfully convicted — falls beyond the scope of the inquiry, which was announced in 2023 by the health secretary in the last Conservative government.

The inquiry’s narrow scope prompted 24 experts, who emphasized that they had no connection to Ms. Letby or her family, to send a letter last month to the current health secretary, Wes Streeting, and the justice secretary, Shabana Mahmood.

In excerpts provided to The New York Times by a representative of the signatories, they wrote, “While we acknowledge the gravity of the convictions against Ms. Letby, our focus is on the broader implications for patient safety, health-care management and the potential for miscarriages of justice in complex medical cases.”

“Possible negligent deaths that were presumed to be murders could result in an incomplete investigation of the management response to the crisis,” they added, in a letter first reported by The Guardian. “Our goal is not to re-litigate the Letby case, but to ensure that the Thirlwall inquiry is positioned to conduct the most thorough and beneficial investigation possible for the future of neonatal care in the UK.”

Among the signatories are Richard Elston, a fellow of the Royal Statistical Society, and Gillian Tully, an expert in forensic science at Kings College London who served as the forensic science regulator for England and Wales. The signatories declined to release the full letter, saying it was intended to be private.

Medical experts have argued that other factors — including staff shortages, crowded conditions in the ward, poor equipment, or management problems — could have contributed to the abnormally high number of babies dying or becoming seriously ill in the unit where Ms. Letby worked. The National Health Service was under acute pressure during this period, after years of constrained budgets and understaffing.

Statisticians have criticized the investigation for concluding that because Ms. Letby was on duty during a cluster of these incidents, she must have been responsible for them.

The case hinged on her being held responsible for administering an overdose of insulin to two babies, but both survived, and several medical experts said the test results used to suggest insulin had been artificially administered were not reliable as evidence of a crime.

There were no witnesses to Ms. Letby killing or mistreating babies under her care, and she has denied murdering anyone. While her lawyers tried to discredit the prosecution’s evidence, they did not present their own evidence.

Phil Hammond, a retired doctor in the National Health Service who has written about the case as medical correspondent for Private Eye magazine, pointed out that the defense only appointed one expert and never called him. “Unsurprisingly, the evidence was very one-sided,” he said. The prosecution, he added, “were shooting at an open goal.”

Mr. Hammond has signed a separate open letter to Prime Minister Keir Starmer, which calls for a “full forensic review of the evidence used in the Letby case.” He said he was not sure whether Ms. Letby did what she was convicted of, but he does not believe she got a fair trial, a position held by a number of other people involved in the case. That could pose a challenge to an inquiry that was created on the basis that she was guilty.

Ms. Letby has been convicted twice: in August 2023, on seven counts of murder and six counts of attempted murder; and last July, on a single count of attempted murder, in a retrial after the jury did not reach a verdict on that charge in the first trial.

News coverage of the case included sensational details like her anguished handwritten notes. She wrote, “I killed them on purpose because I’m not good enough to care for them,” and in capital letters, “I AM EVIL I DID THIS.” Yet on the same piece of paper she had also scrawled: “I haven’t done anything wrong,” “I feel very alone + scared,” and “slander discrimination.”

Reporting on the case was cut off at critical junctures because of restrictions under English law on news that could prejudice a jury. Last September, the restrictions were reimposed after the public prosecutor for England and Wales announced it would seek to retry the attempted murder charge. They have since been lifted.

In May, The New Yorker published a highly critical 13,000-word investigation of the case. The magazine’s publisher, Condé Nast, blocked access to online readers in Britain, for fear of being held in contempt, which can be punished with a fine or prison sentence, although the magazine was available in print and on the magazine’s app. British papers, like The Guardian and The Times of London, have since run articles questioning the evidence, as have broadcasters.

For all the concerns being raised, however, some doubt the new Labour government will delay or expand the scope of the inquiry.

“There isn’t a political energy or head space to do it,” Mr. Hammond said. “It would be so embarrassing if the biggest baby-killer case in British history was found to be unsound.”