Lucy Letby (born 4 January 1990) is a British former neonatal nurse who murdered seven infants and attempted to murder six others between June 2015 and June 2016. Letby was the focus of suspicion following a high number of infant deaths at the neonatal unit of the Countess of Chester Hospital, shortly after she was qualified to work with children in the hospital's intensive care unit, and owing to her being on duty whenever suspicious incidents took place. Letby was charged in November 2020 with eight counts of murder and ten counts of attempted murder. During her trial, which lasted from October 2022 to August 2023, it was revealed that Letby's methods included injecting the infants with air or insulin, overfeeding them, and physically abusing them with medical tools. She also removed over 250 confidential nursing handover sheets from her workplace which should never have left the hospital, and she falsified patient records to avert suspicion. Several parents and colleagues of Letby had also entered the room during, or soon after, an attack. On 21 August 2023, Letby was sentenced to life imprisonment with a whole life order. Letby pleaded not guilty at her trial and told a subsequent Nursing and Midwifery Council disciplinary panel that she is innocent. An application to appeal her conviction was renewed in February 2024 and is due to be heard by the Court of Appeal on 22 April 2024. Unrelated to any appeal, she faces a retrial in June 2024 on the one charge that the jury were unable to reach a verdict on in the original trial. Letby is the most prolific serial killer of children in modern British history; the Cheshire Constabulary now suspects that she may have claimed more victims, including at Liverpool Women's Hospital, where two infants died during her training. Management at the Countess of Chester Hospital were criticised for ignoring warnings about Letby that could have prevented some of the killings. The British government has commissioned an independent statutory inquiry into the circumstances surrounding the murders.