(1) Any person who sends to another person
(a) a letter, electronic communication or article of any description which conveys
(i) a message which is indecent or grossly offensive
(ii) a threat or
(iii) information which is false and known or believed to be false by the sender or
(b) any article or electronic communication which is, in whole or part, of an indecent or grossly offensive nature,
is guilty of an offence if his purpose, or one of his purposes, in sending it is that it should, so far as falling within paragraph (a) or (b) above, cause distress or anxiety to the recipient or to any other person to whom he intends that it or its contents or nature should be communicated.

(2) A person is not guilty of an offence by virtue of subsection (1)(a)(ii) above if he shows
(a) that the threat was used to reinforce a demand made by him on reasonable grounds and
(b) that he believed, and had reasonable grounds for believing, that the use of the threat was a proper means of reinforcing the demand.

(2A) In this section 'electronic communication' includes _
(a) any oral or other communication by means of a telecommunication system(within the meaning of the Telecommunications Act 1984 (c12)); and
(b) any communication (however sent) that is in electronic form.

(3) In this section references to sending include references to delivering or transmitting and to causing to be sent, delivered or transmitted and 'sender' shall be construed accordingly.

(4) A person guilty of an offence under this section shall be liable on summary conviction to imprisonment for a term not exceeding six months or to a fine not exceeding level 5 on the standard scale, or to both.

Postal Services Act 2000 section 85

(1) A person commits an offence if he sends by post a postal packet which encloses any creature, article or thing of any kind which is likely to injure other postal packets in course of their transmission by post or any person engaged in the business of a postal operator.

(2) Subsection (1) does not apply to postal packets which enclose anything permitted (whether generally or specifically) by the postal operator concerned.

(3) A person commits an offence if he sends by post a postal packet which encloses-
(a) any indecent or obscene print, painting, photograph, lithograph, engraving, cinematograph film or other record of a picture or pictures, book, card or written communication, or
(b) any other indecent or obscene article (whether or not of a similar kind to those mentioned in paragraph (a)).

(4) A person commits an offence if he sends by post a postal packet which has on the packet, or on the cover of the packet, any words, marks or designs which are of an indecent or obscene character.

(5) A person who commits an offence under this section shall be liable-
(a) on summary conviction, to a fine not exceeding the statutory maximum,
(b) on conviction on indictment, to a fine or to imprisonment for a term not exceeding twelve months or to both.

Communications Act 2003 section 127

(1) A person is guilty of an offence if he-
(a) sends by means of a public electronic communications network a message or other matter that is grossly offensive or of an indecent, obscene or menacing character; or
(b) causes any such message or matter to be so sent.

(2) A person is guilty of an offence if, for the purpose of causing annoyance, inconvenience or needless anxiety to another, he-
(a) sends by means of a public electronic communications network, a message that he knows to be false,
(b) causes such a message to be sent; or
(c) persistently makes use of a public electronic communications network.

(3) A person guilty of an offence under this section shall be liable, on summary conviction, to imprisonment for a term not exceeding six months or to a fine not exceeding level 5 on the standard scale, or to both.

(4) Subsections (1) and (2) do not apply to anything done in the course of providing a programme service (within the meaning of the Broadcasting Act 1990 (c. 42)).

(1) A person who
(a) sends, by means of a public telecommunication system, a message or other matter that is grossly offensive or of an indecent, obscene or menacing character or
(b) sends by those means, for the purpose of causing annoyance, inconvenience or needless anxiety to another, a message that he knows to be false or persistently makes use for that purpose of a public telecommunication system,
shall be guilty of an offence and liable on summary conviction to imprisonment for a term not exceeding six months or a fine not exceeding level 5 on the standard scale or both.
(2) Subsection (1) above does not apply to anything done in the course of providing a programme service (within the meaning of the Broadcasting Act 1990).