The offence is created by section 5 of the Public Order Act 1986:
"(1) A person is guilty of an offence if he:
(a) uses threatening, abusive or insulting words or behaviour, or disorderly behaviour, or
(b) displays any writing, sign or other visible representation which is threatening, abusive or insulting,
within the hearing or sight of a person likely to be caused harassment, alarm or distress thereby."
This offence has the following statutory defences:
(a) The defendant had no reason to believe that there was any person within hearing or sight who was likely to be alarmed or distressed by his action.
(b) The defendant was in a dwelling and had no reason to believe that his behaviour would be seen or heard by any person outside any dwelling.
(c) The conduct was reasonable.
And also, it would seem, has given the cnuts a message that, should they wish to gratuitously charge somebody after they have failed to achieve what they set out to in the first place (ie do the little ****** for drugs), then they are on a hiding to nothing.
That was discussed on Arrse by a couple of the resident coppers a few years ago. It seemed that they believed that someone had to be offended by the sweary words and coppers wouldn't be so easily shocked. The other copper commented that the SOP was to say that an approaching mother had been so shocked and had hurried her child to the other side of the street.
I was so impressed by (what appeared to be) two coppers exchanging tips on committing perjury on a public forum, that i looked it up on Google, which directed me to some police forum, where it had also being discussed. It seems that someone being offended was an urban myth. The Section 5 Public Order Act (or whatever) simply says it is an offence to swear on a public street where someone could be offended. Swearing in a building wasn't an offence.
If it was the Section 5 thingy he'd been charged with, I think you'll find it is an offence, whatever Mr Judge might decide. I can't be arsed to look it up. It could probably be overturned if the CPS wanted to appeal. They probably won't.
The salient point seems to be missed.
I'm not particularly offended by swearing, however when someone is outside your house, or in your ward, dole office etc swearing like a trooper and doing their dinger, surprisingly enough people phone the police and expect them to deal with it as professional witnesses. The sticky point comes(over the boarder, where smith vs Docherty concluded that the police can't be offended by "such truculent language") when no one wants to give a statement and we walk away leaving said person continuing their behaviour, whilst the phonee, calls us all the useless bastards under the sun, despite it now being enshrined in law.
The issue with law and order lies with sheriffs and judges who have no conception of the problems in the country at street level.