«(iii) Where (and only where) there is a reasonable belief that there are no other means whatsoever whereby a breach of the peace or
imminent breach of the peace can be obviated, the lawful exercise by third parties of their rights may be curtailed by the police; (iv) this is a test of necessity which it is to be expected can only be justified in truly extreme and exceptional circumstances; and (v) the action taken must be both reasonably necessary and proportionate.»
«(i) Where a
breach of the
peace is taking place, or is reasonably thought to be
imminent, before the police can take any steps which interfere with or curtail in any way the lawful exercise
of rights by innocent third parties they must ensure that they have taken all other possible steps to ensure that the
breach, or
imminent breach, is obviated and that the rights
of innocent third parties are protected.»