(1) This section applies if a surveillance device warrant is issued to a senior officer of a law enforcement agency.
(2) If the senior officer to whom the warrant is issued, or the law enforcement officer who is primarily responsible for executing the warrant, believes that use of a surveillance device under the warrant is no longer necessary for the purpose of enabling evidence to be obtained of the commission of the relevant offence or the identity or location of the offender, the officer must inform the chief executive officer of the law enforcement agency immediately.
(3) If the chief executive officer of the law enforcement agency is satisfied, whether because of subsection (2) or otherwise, that the use of a surveillance device under the warrant is no longer necessary for the purpose of enabling evidence to be obtained of the commission of the relevant offence or the identity or location of the offender, the chief executive officer—(a) must take the steps necessary to ensure that use of the surveillance device authorised by the warrant is discontinued as soon as practicable; and(b) must give written notice of that fact to the public interest monitor.
(4) If notice is given under subsection (3) (b) for a surveillance device warrant, the warrant stops having effect other than to the extent it authorises the removal of a surveillance device and any enhancement equipment.
(5) Also, if the chief executive officer is notified that the warrant has been revoked by a judge or magistrate under section 334 (1) , the chief executive officer must take the steps necessary to ensure that use of the surveillance device authorised by the warrant is discontinued immediately.