Parliament had intended that the dispersal regime under the Anti-social Behaviour Act 2003 s.30 should apply to protests. Where an authorisation had been validly made within the terms of the Act, it might be used to empower police officers to issue dispersal directions to a group of people acting in an anti-social manner of a kind not contemplated at the time the authorisation was made.

[2006] EWCA Civ 1118