s 142 Power of justice of the peace to authorise entry and search of premises for offensive weapons.
(1) If on an application made by a constable a justice of the peace (including, in Scotland, the sheriff) is satisfied that there are reasonable grounds for believing— (a) that there are on premises specified in the application— (i) knives such as are mentioned in section 1(1) of the Restriction of Offensive Weapons Act 1959; or (ii) weapons to which section 141 above applies; and (b) that an offence under section 1 of the Restriction of Offensive Weapons Act 1959 or section 141 above has been or is being committed in relation to them; and (c) that any of the conditions specified in subsection (3) below applies, he may issue a warrant authorising a constable to enter and search the premises. (2) A constable may seize and retain anything for which a search has been authorised under subsection (1) above. (3) The conditions mentioned in subsection (1)(c) above are— (a) that it is not practicable to communicate with any person entitled to grant entry to the premises; (b) that it is practicable to communicate with a person entitled to grant entry to the premises but it is not practicable to communicate with any person entitled to grant access to the knives or weapons to which the application relates; (c) that entry to the premises will not be granted unless a warrant is produced; (d) that the purpose of a search may be frustrated or seriously prejudiced unless a constable arriving at the premises can secure immediate entry to them. (4) Subsection (1)(a)(i) shall be omitted in the application of this section to Northern Ireland.