3.—(1) If the senior police officer present at the scene reasonably believes that two or more persons are trespassing on land and are present there with the common purpose of residing there for any period, that reasonable steps have been taken by or on behalf of the occupier to ask them to leave and—
(a)that any of those persons has caused damage to the land or to property on the land or used threatening, abusive or insulting words or behaviour towards the occupier, a member of his family or an employee or agent of his; or
(b)that those persons have between them six or more vehicles on the land,
he may direct those persons, or any of them, to leave the land and to remove any vehicles or other property they have with them on the land.
(2) Where the persons in question are reasonably believed by the senior police officer to be persons who were not originally trespassers but have become trespassers on the land, the officer must reasonably believe that the other conditions specified in paragraph (1) are satisfied after those persons became trespassers before he can exercise the power conferred by that paragraph.
(3) A direction under paragraph (1), if not communicated to the persons referred to in paragraph (1) by the police officer giving the direction, may be communicated to them by any constable at the scene.
(4) If a person knowing that a direction under paragraph (1) has been given which applies to him—
(a)fails to leave the land as soon as reasonably practicable; or
(b)having left again enters the land as a trespasser within the period of 3 months beginning with the day on which the direction was given,
he commits an offence and is liable on summary conviction to imprisonment for a term not exceeding 3 months or a fine not exceeding level 4 on the standard scale, or both.
(5) A constable in uniform who reasonably suspects that a person is committing an offence under this Article may arrest him without a warrant.
(6) In proceedings for an offence under this Article it is a defence for the accused to show—
(a)that he was not trespassing on the land;
(b)that he had a reasonable excuse for failing to leave the land as soon as reasonably practicable or, as the case may be, for again entering the land as a trespasser; or
(c)that, at the time the direction was given, he was under the age of 18 years and was residing with his parent or guardian.
(7) For the purposes of this Article and Article 4—
“land” does not include—
buildings other than—
agricultural, livestock or poultry buildings within the meaning of paragraphs 2 and 3 of Schedule 1 to the Rates (Northern Ireland) Order 1977 (NI 28); or
scheduled monuments within the meaning of the Historic Monuments and Archaeological Objects (Northern Ireland) Order 1995 (NI 9);
land forming part of a road within the meaning of Article 2(2) of the Roads (Northern Ireland) Order 1993 (NI 15);
“property”, in relation to damage to property on land, means property within the meaning of Article 12(1) of the Criminal Damage (Northern Ireland) Order 1977 (NI 4) and “damage” includes the deposit of any substance capable of polluting the land.