(2)An offence under this section may be committed in a public or a private place, except that no offence is committed where the words or behaviour are used, or the writing, sign or other visible representation is displayed, by a person inside a dwelling and the person who is harassed, alarmed or distressed is also inside that or another dwelling.
(3)It is a defence for the accused to prove—
(a)that he was inside a dwelling and had no reason to believe that the words or behaviour used, or the writing, sign or other visible representation displayed, would be heard or seen by a person outside that or any other dwelling, or
(b)that his conduct was reasonable.