A recent American case about television’s “fleeting expletives” (unscripted swear words) involved the key question of whether the word “f--k” was “presumptively indecent and profane”. Was it so bad that anyone who used the word should be punished regardless of the context in which it was broadcast? Punishment can include imprisonment for two years.

In Fox v Federal Communications Commission, a Federal appeal court rejected an FCC decision of indecency against the Fox television network. The court ruled that the FCC's new policy of cracking down on even fleeting, unplanned swearing was "arbitrary and capricious".

At issue, among other things, was Fox's broadcast of the Billboard Music Awards in December, 2002, at which the singer Cher used the phrase "F--k 'em", and the 2003 awards at which Nicole Richie asked: "Have you ever tried to get cow s--t out of a Prada purse? It’s not so f---ing simple.”

In a 53-page judgment, the court rejected the FCC's principle that the words "f--k" and "s--t" always have a sexual and excretory connotation. The law report notes (page 27): “President Bush’s remark to the British Prime Minister Tony Blair that the United nations needed to 'get Syria to get Hezbollah to stop doing this s--t' and Vice President Cheney’s widely reported 'F--k yourself' comment to Senator Patrick Leahy on the floor of the US Senate”.

After all, if the FCC were right that a word could never have a variety of connotations we’d have to censor the Vice President as D--k Cheney.

Britain hasn’t had a policy to punish broadcasters for fleeting expletives. On Saturday November 13, 1965, in a live debate on a BBC programme, the drama critic Kenneth Tynan, speaking about censorship, became the first person to use the f-word on British TV. He said: "I doubt if there are any rational people to whom the word 'f--k' would be particularly diabolical, revolting or totally forbidden." This caused something of an uproar. Some MPs condemned the incident, and Mary Whitehouse, founder of the Clean-up TV Campaign, wrote to the Queen to complain, but no legal actions followed. The BBC apologised and noted that the word was unscripted.

The line between what is shocking and what is corrupting is difficult to draw. Under section 6(1) of the Broadcasting Act 1990, independent broadcasters must not include anything in their programmes which offend against “good taste and decency”, and the BBC must operate under effectively the same rules. In 2002, the House of Lords decided that it was lawful for the BBC to have refused to show an anti-abortion party’s election broadcast which graphically depicted an abortion. The Lords said that a court shouldn’t carry out its own “balancing exercise” between the need for freedom of political speech and the need to protect the public from being unduly distressed at home. Such judicial balancing wasn’t required because Parliament had already decided where the balance should be held: that nothing must be broadcast which “offends against good taste or decency”.

The concern to control spontaneous use of swearing – the fleeting expletives – arises from a culture of rules that was formed to deal with more planned activities like scripted theatre and film. Film censorship has odd legislative origins. The Cinematograph Act 1909 was passed as a safety measure to prevent real inflammatory stuff: fires. Under the law, local authorities were empowered to licence cinemas if the premises were safe. Then, in a 1910 case involving the marvellously named London cinema, the Bermondsey Bioscope, the High Court ruled that, under the Act, a council could impose any reasonable condition on cinemas, not just conditions about physical safety.

The first film to be banned was one later that year showing the world heavyweight title fight between James L. Jeffries and Jack Johnson. Jeffries had been persuaded to return from retirement to regain the title "for the white race". He was knocked out by Johnson, who was black. The authorities thought that the film would "demoralise" British viewers.

Censorship in the UK has, at times, been as rigorous as the approach favoured by the American FCC, but in a quaint British way, and with telling preoccupations. In July, 1948, the Head of Variety at the BBC issued an order to broadcasters which stated: “There is an absolute ban on the following: jokes about lavatories . . . marital infidelity, effeminacy in men, immorality of any kind . . . chambermaids, fig-leaves, prostitution, ladies underwear, animal habits, e.g. rabbits, lodgers, [and] commercial travellers.”

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