Northern Ireland (Emergency Provisions) Act 1991

3 (1) A justice of the peace or, in Scotland, a sheriff may, on an application made by an authorised investigator, issue a warrant under this paragraph if he is satisfied, in relation to any documents, that there are reasonable grounds for believing—

(a) that—

(i) a person has failed to comply with an obligation under paragraph 2 above to produce them;

(ii) it is not practicable to serve a notice under that paragraph in relation to them; or

(iii) service of such a notice in relation to them might seriously prejudice the investigation; and

(b) that they are on premises specified in the application.

(2) A warrant under this paragraph shall authorise any constable (using such force as is reasonably necessary)—

(a) to enter and search the premises; and

(b) to take possession of any documents appearing to be documents of a description specified in the application or to take in relation to any documents so appearing any other steps which may appear to be necessary for preserving them and preventing interference with them.

(3) An application under this paragraph in Northern Ireland shall be made by a complaint on oath, in England and Wales by information on oath and in Scotland supported by evidence on oath.

(4) A warrant issued by a sheriff shall be authority for opening lockfast places and may authorise persons named in the warrant to accompany a constable who is executing it.

(5) The power exercisable by a justice of the peace under this paragraph in Northern Ireland may be exercised by the Secretary of State if, in addition to being satisfied as to the matters mentioned in sub-paragraph (1) above, it appears to him that the information which it would be necessary to provide in support of an application under that sub-paragraph would, if disclosed, be likely to place any person in danger or prejudice the capability of members of the Royal Ulster Constabulary to investigate acts of terrorism or the activities of a proscribed organisation.