Image caption Does the ubiquity of swearing mean there is no point gagging it?

A High Court judge has ruled that people should not be punished for hurling obscenities in public because such words are now so common they no longer cause distress. Should the courts punish profanity?

Your mother might demand that you wash your mouth out.

But swearing in public, previously a criminal offence across the UK, appears to no longer offend the legal system as much as it once did.

Or so, at least, it would appear after Mr Justice Bean upheld the appeal of a defendant who was convicted for repeatedly using an expletive while being searched by police. The judge ruled that officers heard the term in question too frequently to be offended by it.

The decision, which has been strongly criticised by the Police Federation, follows a row over guidance issued by the Metropolitan Police, which advised that the courts were unlikely to rule that officers would be caused distress by most swear words.

London Mayor Boris Johnson has called for the advice to be revoked, and the Home Office is holding a consultation into section five of part I of the Public Order Act 1986, which had previously been used to prosecute those who swore at officers.

At the heart of the issue is the question of whether - for better or worse - terms that would once have been considered taboo are now so commonplace that they have lost their power to shock, giving the courts no business to tackle them.

A new swearword BBC Radio 4's PM programme is appealing for listeners to send in new swear words of their own

They must not be compounds of existing swear words

Suggestions should be sent to pm@bbc.co.uk

It's a proposition that is strongly - but politely - rejected by Peter Foot, chairman of the National Campaign for Courtesy, which lobbies for better manners in British life.

He has no interest in banning swearing in the privacy of one's home or in like-minded company. But he argues that the violence of some phrases and the upset they can cause mean it is right in certain circumstances for the courts to intervene.

"Obviously it can't be a legal thing if you hit your thumb with a hammer instead of the nail," Foot says.

"But the police have to be able to judge whether someone is being particularly abusive. And of course they would complain when it's combined with an aggressive manner towards them.

"If you want to do it in your own room, that's fine. But if you're in a place where you're in earshot of other people it can be very distressing."

Of course swearing's good. Just in terms of cadence, the way the words fall in a sentence, the poetry of language Ian Martin, Co-writer of The Thick of It (above)

Defenders of swearing may cite their centuries-old right to free speech. In fact, laws against profanity have a long tradition in the UK.

In 1551 the Scottish Parliament banned "sweiring, execrationnis and blasphematioun of the name of God", punishable by a shilling fine or a spell in either prison or the stocks for those who could not pay.

England was initially more tolerant. In 1601 a bill "against usual and common swering" was introduced to the House of Commons, but failed to attract enough support from MPs. However, in 1623 an act was passed against swearing, which was rigorously enforced by the Puritans.

The abolition of censorship in the 1960s gave free expression to many words and phrases which previously had been deeply taboo. However, in recent years efforts have been made to eradicate profanity from British streets.

In 2008, council chiefs in Preston erected signs bearing that most Lancastrian of instructions: "No Effin' and Jeffin'." Police were empowered to hand out fixed penalty notices of up to £80 for public order offences by way of enforcement.

Nor is this the only UK local authority to have attempted to enforce such a clean-air policy. From 2005, new tenants of Brighton and Hove's Hollingdean estate were obliged to sign contracts agreeing not to swear in public. Those who broke this pledge were warned they could lose their homes.

And yet swearing has its enthusiasts, not least in the field of comedy. Though clearly not to everyone's taste, the likes of Peter Cook and Dudley Moore's Derek and Clive sketches and George Carlin's Seven Dirty Words routine have influenced generations of humorists.

One of the most notable examples of this genre is the award-winning BBC political satire The Thick of It. Such was the dextrous use of industrial language by one of the show's writers, Ian Martin, that he was bestowed with the title of "swearing consultant".

Martin would never seek to defend anyone verbally abusing police officers. However, he cautions against blanket attacks on profanity - the lexicon of which, after all, derives power from its own waywardness.

"Of course swearing's good. Just in terms of cadence, the way the words fall in a sentence, the poetry of language," he says.

"Swearing is by definition an aggressive, transgressive act. Its impact depends entirely on context. There's a huge difference between watching someone swear on the telly and watching someone swear outside a primary school.

"In the end the whole 'grown up and clever' argument's a winner, isn't it? If your swearing can make people laugh it's a subversion of the transgression."

If Martin is right and humour undermines the shock value of taboo terms, it might follow that comedy, not the courts, is the best way of tackling verbal abuse.

Of course, others will seek more formal methods of redress. The debate will continue - very courteously, no doubt.