33Exercise of powers
(1)This section applies for the purposes of sections 21 to 30.
(2)A power conferred on a person—
(a)is additional to powers which he has at common law or by virtue of any other enactment, and
(b)shall not be taken to affect those powers or Her Majesty’s prerogative.
(3)A constable or member of Her Majesty’s forces may if necessary use reasonable force for the purpose of exercising a power conferred on him.
(4)Where anything is seized it may (unless the contrary intention appears) be retained for so long as is necessary in all the circumstances.
(5)A power to search premises conferred by virtue of this Act shall be taken to include power to search a container.
(6)A member of Her Majesty’s forces exercising a power when he is not in uniform shall, if requested to do so by a person at or about the time of exercising the power, produce to that person documentary evidence that he is a member of Her Majesty’s forces.