In the wake of the conflict between police and demonstrators at the G20 summit in London, Clive Anderson and his guests on this week’s edition of Unreliable Evidence for Radio 4, discuss the Law and Protest.

Lord Hoffmann, recently retired as a Law Lord, argues that there has always been a convention that acknowledges that protest will inevitably involve a certain amount of illegal behaviour  - such as trespass, daubing slogans and chaining to railings.  In response, the legal justice system treats such offences leniently.

But he is concerned that the police, in the interests of maintaining order, may be breaking that convention, overusing their powers, particularly when they take pre-emptive action to prevent demonstrations taking place.  And he fears that this may sometimes happen simply to save the cost and trouble of policing a protest.

Tune in to BBC Radio 4 to hear more, Wednesday 20 May at 8pm.