Unlucky numbers: Fighting murder convictions that rest on shoddy stats

LEIDEN, THE NETHERLANDS— When a Dutch nurse named Lucia de Berk stood trial for serial murder in 2003, statistician Richard Gill was aware of the case. But he saw no reason to stick his nose into it. De Berk was a pediatric nurse at Juliana Children’s Hospital in The Hague. In 2001, after a baby died while she was on duty, a colleague told superiors that De Berk had been present at a suspiciously high number of deaths and resuscitations. Hospital staff immediately informed the police. When investigators reexamined records from De Berk’s shifts, they found 10 suspicious incidents. Three other hospitals where De Berk had previously worked added another 10. The probability of such a pattern happening by chance was one in 7 billion, the police said. De Berk was arrested on 13 December 2001, suspected of murdering five children. Newspapers called her a “murder nurse” and an “angel of death.” Gill, then working as a statistics professor at Leiden University, remembers his wife telling him about a “witch trial” and saying, “They’re using statistics; you should get involved, do something useful.” But Gill knew the statistician working on the case and considered him a decent, careful person. “So I thought I didn’t have to. And anyway, I was obsessed with quantum mechanics,” he says. In 2003, De Berk was found guilty of four murders and three attempted murders and sentenced to life in prison. An appeals court convicted her again in 2004. T...
Source: Science of Aging Knowledge Environment - Category: Geriatrics Source Type: research