When originally confronted with her error, Hedges had no answer other than that she had missed it. She repeated this in evidence. When pressed by Orlando Pownall QC, Hedges said: “I’ve been thinking about it overnight and I think it’s unlikely that I wouldn’t have seen it.1 My explanation is that I would have KM-tested2 it and produced a negative result.”

This suggests that either the staining which was clearly visible to the naked eye was not there when she examined the trainer, or the presumptive test was negative. Both interpretations are fanciful. Original photographs show the stains clearly and if the KM-tests were negative, where are her laboratory notes of the tests that she claims she would have conducted and why did she fail to come up with this explanation earlier? The question of how a presumptive test for possible blood-staining on a large area that was in fact blood could test negative also seems to have escaped her. Although false negatives can occur, they don’t in the circumstances of this case. It is a rare phenomenon that is unlikely to only be remembered as an afterthought.

Four innocent boys stood trial for the same crime in 2002. That trial collapsed due to the unreliability of the key witness referred to as Bromley. John Sentamu, now Archbishop of York, headed an inquiry into police handling of vulnerable child witnesses like Bromley that resulted in recommendations.

The Home Office review focused on how the vital evidence that secured the convictions was missed in the first place. There was no investigation into how the Damilola Taylor Inquiry was mishandled in the first place. Hedges’ error does not explain how the innocent original defendants were allowed to stand trial years ago. Neither the Metropolitan police, nor its police authority have announced any plans for an inquiry into what went wrong – errors that almost derailed justice permanently. Indeed had wrongful convictions been obtained then through highly dubious methods, the Preddie brothers would never have been brought to justice.