- guardian.co.uk, Thursday June 23 2005 13.38 BST
A senior paediatrician whose expert testimony led to mothers being wrongly convicted of murdering their children used unreliable statistics that should never have been presented as evidence of child abuse, a disciplinary hearing was told today.
The General Medical Council (GMC) heard that Professor Sir Roy Meadow, whose expert evidence helped jail Sally Clark and Angela Cannings, did not portray the odds of two or more cot deaths occurring in one family in the right context.
Professor Peter Fleming, who led a national inquiry into sudden infant death, told the GMC hearing in London that the study's findings were never intended to be used to show whether a child had died from natural causes or deliberate harm.
Prof Meadow, 72, cited the Confidential Enquiry into Sudden Death in Infancy in his evidence to the Sally Clark trial, erroneously claiming it showed that the odds of two cot deaths in a family like hers was one in 73 million, when in fact the odds were just one in 77. His evidence was seen as crucial to her wrongful conviction for the murder of her baby sons.
Prof Fleming, infant health and development physiologist at the Institute of Child Health at Bristol University, told the GMC fitness to practice hearing that he was so concerned the study "could be misrepresented" in Mrs Clark's original trial that he wrote to her defence team.
Prof Fleming told the hearing that the "extreme rarity" of a single cot death in an affluent family - one in 8,543 - made the statistic "somewhat unreliable". He said: "It was never intended as a real statistical estimate."
Prof Meadow told the jury that to work out the risk of two cot deaths in a family like the Clarks, one would multiply 8,543 by 8,543 to reach a risk of one in 73 million. With 700,000 live births a year in England, Wales and Scotland, it was an event that would happen by chance "about once every hundred years", he added.
But Prof Fleming said it should have been "quite clear" that the single mention of the one in 73 million statistic in the study was purely illustrative. The statistics in the report were meant to show how genetic factors as well as environmental factors such as parents who smoked came into play, he told the hearing.
The court of appeal cleared Mrs Clark in 2003 after it had emerged the Home Office pathologist Alan Williams had failed to disclose microbiology tests on her son Harry indicating he could have died from natural causes. The judges added that Prof Meadow's statistical error alone should have made her conviction unsafe.
The Royal Statistical Society disputed Prof Meadow's figure, writing to the Lord Chancellor to say that there was no statistical basis for it.
Prof Meadow, a former president of the Royal College of Paediatrics and Child Health, faces being struck off the medical register if found guilty of serious professional misconduct.
The hearing continues.
