Police Powers and Responsibilities Act 2000

A surveillance device warrant may be revoked at any time before the expiry of the period of validity stated in it by—

a Supreme Court judge, if a Supreme Court judge issued the warrant; or

a magistrate, if a magistrate issued the warrant.

Also, a judge or magistrate may revoke a surveillance device warrant after receiving a report under section 357 about the warrant.

A judge or magistrate who revokes a warrant must cause notice of the revocation to be given to the chief executive officer of the law enforcement agency of which the law enforcement officer to whom the warrant was issued is a member.