Criminal Law (Sexual Offences) Act 1993
Powers of arrest.
( a) arrest that person without warrant, or
( b) require him to give his name and address and, if the person fails or refuses to do so or gives a name or address that the member reasonably suspects to be false or misleading, the member may arrest that person without warrant.
(2) A person who fails or refuses to give his name or address when required under subsection (1), or gives a name or address which is false or misleading, shall be guilty of an offence and shall be liable on summary conviction to a fine not exceeding £500.