The family of Ethel Hall, an 86-year-old who died at Leeds General Infirmary in 2002, are calling for a retrial of Colin Norris, the Scottish nurse convicted of her murder and those of three other patients. A new BBC Disclosure podcast reveals growing doubts within the family about Norris's guilt, particularly regarding the medical evidence used to convict him. The case has gained prominence amid similar concerns about the conviction of neonatal nurse Lucy Letby, highlighting broader questions about the reliability of medical evidence in criminal trials.

Norris was convicted in 2008 of killing four patients by insulin injection and attempting to kill two more. His conviction centred on hypoglycemia (critically low blood sugar), which Hall experienced whilst recovering from a broken hip. New scientific evidence has since emerged suggesting hypoglycemia in frail elderly people is more common than previously thought, potentially misleading the jury at trial. The BBC podcast suggests an alternative explanation: that a strong opioid prescribed to Hall for post-operative pain may have induced her coma, with insulin meant for another patient possibly administered in error before the fatal blood sample was taken. Despite losing two appeals, Norris (now known as Colin Campbell) continues to maintain his innocence, supported by his mother and Ethel Hall's family, who have called for a fair retrial.