One day – if it's not happening already – they will teach Trafigura in business schools. This will be the scenario for aspiring MBAs. You are in charge of a large but comfortably anonymous trading company based in London and you have a tiresome PR problem. Three thousand miles away there are 30,000 Africans in one of the poorest countries in the world claiming to have been injured by your company dumping toxic sludge. You are being hit by one of the biggest lawsuits in history. Worse, you now have a bunch of journalists on your case.

What to do? The business school textbooks will advocate a mix of carrot and stick. In charge of your carrot you hire Lord (Tim) Bell, who once performed a similar role on behalf of Mrs Thatcher. He will be in charge of attempts to reposition positive public perceptions of the Trafigura brand. He might, for instance, suggest you become an official sponsor of the British Lions tour of South Africa and an arts prize. And in charge of your stick you hire Britain's most notorious firm of libel lawyers, Messrs Carter-Ruck, who like to boast of their reputation for applying chloroform over the noses of troublesome editors.

For a while all goes well, especially on the stick front. Carter-Ruck spray threatening letters around newsrooms from Oslo to Abidjan. They launch an action against the BBC. And they persuade a judge to suppress a confidential but embarrassing document which has fallen into journalists' hands. A new term is coined: "super-injunctions", whereby the existence of court proceedings and court orders are themselves secret.

Nice work, large cheques all round. But the plan began to unravel rather rapidly on Monday when it transpired that an MP, Paul Farrelly, had tabled a question about the injunction and the awkward document in parliament. That was bad enough, what with the nuisance of 300-odd years of precedent affirming the right of the press to report whatever MPs say or do. There was a tiresomely teasing story on the Guardian front page. And then there was Twitter.

It took one tweet on Monday evening as I left the office to light the virtual touchpaper. At five past nine I tapped: "Now Guardian prevented from reporting parliament for unreportable reasons. Did John Wilkes live in vain?" Twitter's detractors are used to sneering that nothing of value can be said in 140 characters. My 104 characters did just fine.

By the time I got home, after stopping off for a meal with friends, the Twittersphere had gone into meltdown. Twitterers had sleuthed down Farrelly's question, published the relevant links and were now seriously on the case. By midday on Tuesday "Trafigura" was one of the most searched terms in Europe, helped along by re-tweets by Stephen Fry and his 830,000-odd followers.

Many tweeters were just registering support or outrage. Others were beavering away to see if they could find suppressed information on the far reaches of the web. One or two legal experts uncovered the Parliamentary Papers Act 1840, wondering if that would help? Common #hashtags were quickly developed, making the material easily discoverable.

By lunchtime – an hour before we were due in court – Trafigura threw in the towel. The textbook stuff – elaborate carrot, expensive stick – had been blown away by a newspaper together with the mass collaboration of total strangers on the web. Trafigura thought it was buying silence. A combination of old media – the Guardian – and new – Twitter – turned attempted obscurity into mass notoriety.

So this week's Trafigura fiasco ought to be taught to aspiring MBAs and would-be journalists. They might nod in passing to the memory of John Wilkes, the scabrous hack and MP who risked his life to win the right to report parliament. An 18th-century version of crowd-sourcing played its part in that, too.