A Twitter user posted details Sunday of six instances of what the blogger said were injunctions obtained by television and sports stars to cover up affairs or prevent the publication of revealing photographs.
One of the celebrities named, socialite Jemima Khan, used her own Twitter feed to deny an allegation that she had obtained a super injunction to prevent intimate pictures of her and TV presenter Jeremy Clarkson from being published.
"OMG - Rumour that I have a super injunction preventing publication of "intimate" photos of me and Jeremy Clarkson. NOT TRUE!" she tweeted.
Super injunctions prevent the media from reporting not only details of a story but even the existence of the injunction.
They have their legal basis in the UK's 1998 Human Rights Act but have given rise to concerns of a creeping privacy law made by the courts and favoring the famous and wealthy.
"It's rich man's justice," said media lawyer Mark Stephens, a partner at London-based law firm Finers Stephens Innocent, noting that not a single woman was known to have obtained such an injunction.
Stephens estimated that about 200 super injunctions had been issued in the past three to four years. Their cost of more than 100,000 pounds ($164,000) each puts them out of most people's reach.
Public debate over super injunctions was rekindled last month when prominent BBC journalist Andrew Marr confessed that he had obtained one in 2008 to prevent reporting of an extra-marital affair he had had.
Stephens, an outspoken pro-media lawyer who has represented celebrities including WikiLeaks founder Julian Assange, said incidents like the weekend Twitter leak showed the super injunction was outdated.
"The superinjunction is becoming unsustainable because people are just breaking it," he said.
His sentiments were echoed by intellectual property and media lawyer Keith Arrowsmith, a partner at Manchester-based law firm Ralli Solicitors.
"The fact that anyone can set up these feeds without anyone checking the identity of the author undermines the credibility of super injunctions. People on Twitter feel as though they can publish anything and it doesn't matter," he said.
Twitter had no immediate comment on the matter. The tweets were still on the site Monday afternoon, almost 24 hours after they were first published.
ECHOES OF SPYCATCHER
Both lawyers compared the current situation with the notorious 1980s Spycatcher case, in which the British government tried to ban ex-intelligence officer Peter Wright from publishing his autobiography.
The book was published in Australia and in many other foreign countries and was smuggled into Britain. The UK government eventually gave up its attempt to ban it.
One of the best-publicized uses of a super injunction was the case of shipping company Trafigura in 2009, which forbade discussion of allegations the company had dumped toxic waste in Ivory Coast.
"The underlying problem with the current law is that the courts are being used to conceal the truth," Liberal Democrat member of parliament John Hemming wrote in an email to Reuters. Hemming is compiling a report on super injunctions.
"I know of a number of cases where the truth that is being concealed involves serious misbehavior by the authorities rather than the peccadilloes of celebrities. That is where there is a real danger in the current position," he added.
Stephens said the author of the weekend tweets could expect "a knock on the door from the lawyers" in the next 48 hours for contempt of court.
But Arrowsmith stressed that this would not help the people who had been outed.
"In the past, for example, if someone had got wind that the News of the World was planning to break a story Sunday, we could try to agree a way forward, and, if that failed, approach the court for a ruling."
"With international instant messaging it's too late, the cat is out of the bag," he said.
Arrowsmith said Twitter itself, as a U.S.-based organization, would be hard for UK courts to pursue.
"If you're going to have a super injunction, you've got to have a international super court to enforce it," he said.
(Additional reporting by Olesya Dmitracova; Editing by Steve Addison)
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