21Use of reasonable forceS
(1)This section applies where no permission has been given by an occupier of premises (or another person with the authority to do so) for an enforcement officer to take action under section 18 or 20.
(2)A constable may use reasonable force, or authorise the use of reasonable force by an enforcement officer or by any person assisting the officer, when action is being taken under section 18 or 20—
(a)if the sheriff grants a warrant for the use of reasonable force and the constable accompanies the enforcement officer, or
(b)where no application for a warrant has been made, only if the constable accompanies the officer and reasonably believes that there is a real and substantial risk that delay in seeking a warrant would defeat or prejudice the purpose of taking action.
(3)Despite subsection (2), a constable must not authorise an enforcement officer or any person assisting the officer to use force against an individual.
(4)The sheriff may grant a warrant under this section on the application of an enforcement officer only if satisfied that the use of reasonable force is necessary for the purpose of taking action under section 18 or 20.
(5)A warrant granted under this section expires—
(a)when it is no longer required for the purpose for which it is granted, or
(b)if earlier, on the expiry of such period as may be specified in it.