THE PHRASE “shaken baby syndrome” evokes a powerful image that has stalked parents since Louise Woodward. Yet in Court 4 of the Court of Appeal, three of the most eminent brains in the land are sifting through research that suggests there is no such thing. Each of the four cases they are considering is different. But if the appeals succeed, 90 other convictions could be overturned — a miscarriage of justice would be uncovered that would make the Birmingham Six disaster look like a skirmish.

In the case of Lorraine Harris, jailed for supposedly shaking her baby son to death on the very night that she had called out her doctor because the baby was having breathing difficulties after an immunisation, one wonders what kind of society can have even brought such charges. She was freed when it was proved that her son had a blood disorder, but she is still banned from seeing her other child.

The presumption of guilt on the basis of flimsy science produced not only the SBS cases but also the cot-death accusations made by Professor Sir Roy Meadow, who goes before the General Medical Council tomorrow accused of gross professional misconduct, and another syndrome called metaphyseal fracture. In all three, hysteria seems to have overtaken sound science.

The good work done by Dr David Southall in the 1980s — he videoed mothers smothering their babies — also sowed an evil seed of suspicion. Social services and doctors who feared that abuse was going undetected groped for ways to spot it and made a fatal leap from particular injuries suffered by some abused children to a generalised dogma that such injuries were incontrovertible proof of abuse.

Meadow’s infamous rule — that “one cot death in a family is a tragedy, two is suspicious and three is murder” — was junked after the courts freed Sally Clark and prompted a review of cases involving Munchausen’s Syndrome by Proxy. But for years it gave juries a formula to hang on to. The dogmatic approach to SBS cases was strikingly similar. Dr John Caffey used the term to describe a trio of injuries he saw in many abused children: brain swelling, bleeding around the brain and the retina. Although he later described the evidence as “meagre”, doctors routinely jumped to the conclusion that any child with such haemorrhages must have been shaken, even if there were no other signs of abuse.

The British Medical Journal last year described a healthy 14-month-old taken to hospital with a severe head injury after a TV fell on him at home. Despite the father’s repeated and consistent account, Social Services removed the child’s three-year-old brother because the injuries were considered diagnostic of shaking. Scientists found that such a diagnosis was “not supported by objective scientific evidence”.

SBS “experts” use graphic images — a child’s injuries could have been caused only by an impact similar to a high-speed car crash or a fall from a two or three-storey building — that leave juries in no doubt that the carer must have intended serious harm. Parents’ protestations of innocence are taken as further evidence of guilt and the number of successful convictions bolsters belief in the syndrome.

Only Dr Jennian Geddes, who became alarmed by the number of shaken babies in families with no history of abuse, stopped to think. When she compared the brains of 53 children thought to have been shaken with those of car-crash victims, she found that 50 had no serious head injury — including the daughter of Ray Rock, now in jail for murder. She and others now believe that a wide range of causes, some natural, produce SBS symptoms.

“The abiding impression,” said Lord Justice Judge in his historic verdict on Angela Cannings, “is that a great deal about death in infancy and its causes remain unknown.” Why, then, do we strive so hard to claim knowledge we do not possess? A senior judge told me recently that I was asking the wrong question by insisting on standards for expert witnesses. “Galileo would never have got accreditation,” he said. “No one would have found him credible.”

Our lazy faith in “experts” is particularly dangerous in family courts whose deliberations are secret. Parents who have taken their children to casualty are being accused of abuse on the basis of skeletal X-rays that show a “metaphyseal fracture”: a misleading term — since this is not a fracture but a tiny, painless abnormality at the end of the bone — but one that must sound gratifyingly alarming in court.

A small but powerful group of radiologists believes that metaphyseal fractures are caused by parents twisting and wrenching a child’s limbs — even if there are no bruises, cuts or broken bones. In this month’s Journal of the Royal Society of Medicine Dr James LeFanu argues that such fractures may well be normal variants. X-rays of the bones of 78 cot-death babies showed most had metaphyseal fractures but no fractured bones. A support group set up by accused parents is getting one new call a week. Last week a mother who took her baby to hospital with a nosebleed was accused of abuse after an X-ray showed three metaphyseal fractures. The radiologist said that the mother was depressed, a diagnosis he was not remotely qualified to make.

We cannot know how many children are put in care because of metaphyseal fracture. But one parent says that “on a Monday the county courts look like the M25: parent A, B, C versus the local authority”. Perhaps Michael Mansfield, QC, when he concludes his arguments against shaken baby syndrome, could turn his wit to the fractures that are not fractures in bones, but in the crazed mind of a State that has gone too far.

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