Move is designed to draw line under scandal but legal experts say it ‘must never be seen as a precedent’

Hundreds of post office operators are to have their convictions quashed by parliament within months in an unprecedented move designed to draw a line under one of the biggest miscarriages of justice in British history.

Senior lawyers said, however, that the decision to pass a bill overturning so many court verdicts was constitutionally extraordinary and risked undermining the independence of the judiciary if it was seen as a precedent for future cases.