(1)An officer who is exercising, or is about to exercise, a power conferred by section 14, 15, 16 or 22 must—
(a)give his or her name, and
(b)if not a constable in uniform, produce documentary evidence that he or she is authorised to exercise the power,
if asked to do so by a person entitled to make the request.
(2)The persons entitled to make the request are—
(a)in the case of a power exercisable in relation to an individual, that individual;
(b)in the case of a power exercisable in relation to a vehicle, vessel or aircraft, a person in charge of that vehicle, vessel or aircraft;
(c)in the case of a power exercisable in relation to premises, an occupier of those premises who is on the premises.
(3)An officer need not comply with subsection (1) if it is not reasonably practicable to do so.
(4)An officer may use reasonable force, if necessary, for the purpose of exercising a power conferred on the officer by sections 14 to 25.
(5)A person authorised under section 18(4) to accompany an officer may use reasonable force, if necessary, for the purpose of exercising a power conferred by sections 17 to 25.
(6)The powers conferred on an officer by any of sections 14 to 25 do not affect any powers exercisable by the officer apart from those sections.