British Telecommunications Act 1981

19 Offences due to default of third person

(1) Where the commission by any person of an offence under section 17 or 18 is due to the act or default of some other person, that other person shall be guilty of the offence ; and a person may be charged with and convicted of the offence by virtue of this subsection whether or not proceedings are taken against the first-mentioned person.

(2) In any proceedings for an offence under section 17 or 18 it shall, subject to subsection (3), be a defence for the person charged to prove that he took all reasonable steps and exercised all due diligence to avoid committing the offence.

(3) Where the defence provided by subsection (2) involves an allegation that the commission of the offence was due to the act or default of another person, the person charged shall not, without leave of the court, be entitled to rely on that defence unless, within a period ending seven clear days before the hearing, he has served on the prosecutor a notice in writing giving such information identifying or assisting in the identification of that other person as was then in his possession.

(4) In any proceedings for an offence under section 18 it shall be a defence for the person charged to prove that he is a person whose business it is to publish or arrange for the publication of advertisements and that he received the advertisement for publication in the ordinary course of business and did not know and had no reason to suspect that its publication would amount to an offence under that section.