If a constable in uniform reasonably believes that a person is on his way to an assembly within the area to which an order under section 14A applies which the constable reasonably believes is likely to be an assembly which is prohibited by that order, he may, subject to subsection (2) below—
stop that person, and
direct him not to proceed in the direction of the assembly.
The power conferred by subsection (1) may only be exercised within the area to which the order applies.
A person who fails to comply with a direction under subsection (1) which he knows has been given to him is guilty of an offence.
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A person guilty of an offence under subsection (3) is liable on summary conviction to a fine not exceeding level 3 on the standard scale.