(1) A power to enter premises, or to take action on premises, may not be
exercised unless the person proposing to exercise the power is in possession
of an authority and produces the authority if required to do so by the owner
or occupier of the premises.
(2) The authority must be a written authority
that--
(a) states that it is issued under this Act, and
(b) gives the name of
the person to whom it is issued, and
(c) describes the nature of the powers
conferred and the source of the powers, and
(d) states the date (if any) on
which it expires, and
(e) describes the kind of premises to which the power
extends, and
(3)
However, despite subsections (1) and (2), a police officer exercising a power
to enter premises, or to take action on premises, must produce his or her
warrant card if required to do so by the owner or occupier of the premises in
lieu of an authority.