Expert concern 1

Sir Roy Meadow gave evidence in the murder trial of Sally Clark that the General Medical Council found to be erroneous and misleading. The Court of Appeal criticised the statistical evidence and said it seemed likely that it would have provided "a quite distinct basis upon which the appeal had to be allowed". Meadow's erroneous evidence played a substantial role in sending an innocent woman to jail, and David Southall's failure to mention this is noteworthy ("Justice for a hero of hidden horrors", February 24).

Mr Justice Collins has now provided immunity for medical expert witnesses. In future, they can give evidence when they do not know what they are talking about and make "mistakes" of any magnitude with impunity.

Irresponsible medical evidence is not rare: for example, the GMC found Southall guilty of serious professional misconduct when he presented a theory as a near certainty and wrote a report that implied that a man had killed his sons when Southall did not know the salient facts. Such testimony may in future escape professional oversight: I fail to see how this will improve the quality of medical evidence.

David Bell Nottingham