(1) Subject to the provisions of this section, where a person—
(a) uses threatening, abusive or insulting words or behaviour, or disorderly behaviour; or
(b) displays any writing, sign or other visible representations which is threatening, abusive or insulting,
within the hearing or sight of a person likely to be harassed, alarmed or distressed by such threatening, abusive or insulting words or writing or sign or other visible representation or disorderly behaviour he or she commits an offence and is liable on conviction on indictment to imprisonment for 3 years.
(2) A person commits an offence under subsection (1) if he or she intends his or her words or behaviour or the writing, sign or other visible representation to be threatening, abusive or insulting or, as the case may be, he or she intends his or her behaviour to be or is aware that it may be disorderly.
(3) An offence under this section may be committed in a private or public place, except that no offence is committed where the words or behaviour are used, or the writing, sign or visible representation is displayed, by a person inside a dwelling and the other person is also inside that or another dwelling.
(4) It is a defence for a person charged with an offence under this section to prove—
(a) that he or she had no reason to believe that there was a person within hearing who was likely to be harassed, alarmed or distressed;
(b) that he or she was inside a dwelling and had no reason to believe that the words or behaviour used, or the writing, sign or other visible representation, would be heard or seen by a person outside that or any other dwelling;
(c) that his or her conduct was reasonable.