Hmm I seem to remember that the doctors who actually have to deal with cyclists involved in road accidents took a different view. (Although I should point out that the BMA general council also took the view that making helmets compulsory would have a negative effect overall).
No just some of them. But not the ones who get called as experts by the Courts*.
And the BMA is a Trade Union by the way, not a medical standards body.
* "In this same case, the QC under whose instruction I was privileged to work tried repeatedly to persuade the neurosurgeons acting for either side, and the technical expert opposing me, to state that one must be more safe wearing a helmet than would be the case if one were not. All three refused to do so, claiming that they had seen severe brain damage and fatal injury both with and without cycle helmets being worn."
Brian Walker, CEO of Head Protection Evaluations, the leading UK helmet testing lab writing in the CTC magazine.