The Thirlwall Inquiry, a £19 million investigation launched in 2023, has concluded that multiple failures at the Countess of Chester Hospital allowed nurse Lucy Letby to continue harming infants over a year-long period. Letby, now 36, was convicted in 2023 of seven murders and seven attempted murders of babies in the hospital’s neonatal unit between June 2015 and June 2016. She is currently serving 15 whole-life sentences and is awaiting the outcome of a Criminal Cases Review Commission decision concerning potential miscarriage of justice claims.
The inquiry’s 822-page report, compiled after seven months of evidence and testimony from more than 130 witnesses, highlighted a culture within the hospital that prioritized reputation over patient safety. Lady Justice Thirlwall, who led the inquiry, criticized hospital management for failing to act on clear warning signs, such as abnormal blood test results indicating insulin poisoning and incidents where Letby’s handling of infants was called into question. The report concluded that had appropriate safeguarding measures been taken, including removing Letby from the neonatal unit earlier, some deaths and injuries could have been prevented.
Despite mounting concerns from clinicians starting in mid-2015, Letby remained on the ward until July 2016, after which she was moved to administrative duties. Hospital leadership delayed involving Cheshire Police until May 2017, and Letby was not arrested until July 2018. The inquiry found that families of the affected infants were not kept informed of suspicions during this period, causing further distress.
Among Lady Justice Thirlwall’s 14 urgent recommendations are the installation of baby monitors in neonatal cots and incubators, the placement of CCTV cameras focusing on insulin storage, and enhanced protocols for safeguarding that do not require conclusive proof of staff misconduct before action is taken.
Health Secretary Yvette Cooper acknowledged the report’s findings in the House of Commons, stating that officials have been tasked with developing plans for improved monitoring technologies to help protect vulnerable babies and alleviate parental anxieties.
While Letby maintains her innocence, denying intentional harm to the infants, her convictions were upheld after two trials at Manchester Crown Court. Some medical and legal experts, as well as members of the public and Letby’s family, have expressed skepticism about her guilt or motives, citing her reportedly normal personal life and demeanor. However, juries found evidence sufficient to convict on multiple counts of murder and attempted murder.
The inquiry deliberately did not reassess Letby’s guilt but focused on systemic failings that allowed her actions to continue unchecked. Lady Justice Thirlwall described a "dysfunctional" management structure and lack of understanding of safeguarding procedures within the hospital, emphasizing that the requirement to protect patients should not depend on certainty of wrongdoing.
Separately, Cheshire Police continue to investigate potential criminal liability related to gross negligence and corporate manslaughter among former hospital senior staff. The Health Services Safety Investigations Body has urged the broader NHS to learn from the findings, emphasizing the need for proactive approaches to patient safety that swiftly identify and mitigate risks.