New questions have emerged regarding the conviction of former staff nurse Colin Norris, who was found guilty in 2008 of murdering four elderly patients and attempting to murder a fifth. A new BBC podcast, Disclosure Investigates: Killer on the Ward, has reviewed medical records, police interviews, and new scientific discoveries, suggesting a scenario where the murders may not have occurred.
Norris's conviction stemmed from the death of 86-year-old Ethel Hall in 2002, who was found in a hypoglycemic coma with a high level of insulin in her blood. The investigation subsequently identified three other unexplained hypoglycemic deaths and one attempted murder on Norris's wards.
During Norris's second appeal last year, experts argued that symptoms seen in several patients could occur naturally in elderly, frail individuals. The Crown maintained that the deaths were medically distinct due to refractory low blood sugar readings, which they argued could only be explained by deliberate insulin poisoning.
The BBC investigation found that a diabetic patient on Ethel Hall's ward was being given insulin around the time doctors were trying to save Ethel. An endocrinologist, Professor Joel Zonszein, suggested that if syringes were accidentally switched, the amount of insulin Ethel may have received could have produced the high readings in her blood test, and a dextrose drip could have masked the insulin.