12.—(1) In any proceedings against any person for an offence under regulation 11(1), it is a defence for that person (“P”) to show that P took all reasonable steps and exercised all due diligence to avoid committing the offence.
(2) P may not rely on a defence under paragraph (1) which involves a third party allegation unless P has—
(a)served a notice in accordance with paragraph (3), or
(b)obtained the leave of the court.
(3) The notice must—
(a)give any information in P’s possession which identifies or assists in identifying the person who—
(i)committed the act or default, or
(ii)supplied the information on which P relied, and
(b)be served on the person bringing the proceedings not less than 7 clear days before the hearing of the proceedings.
(4) P may not rely on a defence under paragraph (1) which involves an allegation that the commission of the offence was due to reliance on information supplied by another person unless it was reasonable for P to have relied upon the information, having regard in particular—
(a)to the steps P took, and those which might reasonably have been taken, for the purpose of verifying the information, and
(b)to whether P had any reason to disbelieve the information.
(5) In this regulation, “third party allegation” means an allegation that the commission of the offence was due—
(a)to the act or default of another person, or
(b)to reliance on information supplied by another person.