There is an obvious flaw in this reasoning, as the Royal Statistical Society, protective of its derided subject, has pointed out. The prob-ability calculation works fine, so long as it is certain that cot deaths are entirely random and not linked by some unknown factor. But with something as mysterious as cot deaths, it is quite possible that there is a link—something genetic, for instance, which would make a family that had suffered one cot death more, not less, likely to suffer ‘another.
And since those women were convicted, scientists have been suggest-ing that there may be just such a link.