20.—(1) Subject to sub-paragraphs (2) and (4), in proceedings for an offence under Article 31(1)(c) of the 1978 Order involving a contravention of Part 3 or paragraph 18, it is a defence for a 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 sub-paragraph (1) which involves a third party allegation unless P has—
(a)served a notice in accordance with sub-paragraph (3); or
(b)obtained the leave of the court.
(3) The notice must—
(a)give any information on 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 seven clear days before the hearing of the proceedings.
(4) P may not rely on a defence under sub-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 that 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 believe the information.
(5) In this paragraph, “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.