The head of MI5 has warned we must take the threat of new Islamist atrocities seriously. If the abuse of antiterrorist legislation in the Paul Chambers case is a guide, the people who most need reminding of the importance of seriousness, are MI5's colleagues in the criminal justice system.
The 27-year-old worked for a car parts company in Yorkshire. He and a woman from Northern Ireland started to follow each other on Twitter. He liked her tweets and she liked his and boy met girl in a London pub. They got on as well in person as they did in cyberspace. To the delight of their followers, Paul announced he would be flying from Robin Hood airport in Doncaster to Northern Ireland to meet her for a date.
In January, he saw a newsflash that snow had closed the airport. "Crap! Robin Hood Airport is closed," he tweeted to his friends. "You've got a week… otherwise I'm blowing the airport sky high!"
People joke like this all the time. When they say in a bar: "I'll strangle my boyfriend if he hasn't done the washing up" or post on Facebook: "I'll murder my boss if he makes me work late", it does not mean that the bodies of boyfriends and bosses will soon be filling morgues.
You know the difference between making a joke and announcing a murder, I'm sure. Apparently the forces of law and order do not.
A plain-clothes detective from South Yorkshire Police arrived at Chambers's work. Instead of quietly pointing out that it was best not to joke about blowing up airports, he arrested him under antiterrorist legislation. A posse of four more antiterrorist officers was waiting in reception.
"Do you have any weapons in your car?" they asked.
"I said I had some golf clubs in the boot," Chambers told me. "But they didn't think it was funny. I kept wondering, 'When are they going to slap my wrists and let me go?' Instead, they hauled me into a police car while my colleagues watched."
The Crown Prosecution Service wanted to charge him under the law's provisions against bomb hoaxers, a serious measure aimed at a serious public nuisance. But there had been no hoax. Paul Chambers had not caused a panic at the airport or intended to cause a panic. No one in authority knew about the tweet until some busybody decided to report Chambers.
Instead of displaying a little common sense and letting the matter rest, the CPS dug up an obscure section of the 2003 Communications Act, which makes it an offence to send a "menacing message" over a public telecommunications network.
Chambers pleaded not guilty after reading an outraged article on his case by David Allen Green, one of the new generation of free-speech lawyers. No good did his plea do him. In a Kafkaesque development, the CPS persuaded judge Jonathan Bennett that in the context of terrorist violence his tweet should be taken as a genuine threat, whether he was joking or not and whether the airport knew about the "threat" or not.
The judge gave Chambers a criminal record and ordered him to pay £1,000 in costs and fines.
In Milan Kundera's great anti-communist novel The Joke, the young hero tries to impress a beautiful woman with adolescent bravado. Forgetting what happens to dissenters in Soviet-occupied Czechoslovakia, he writes on a card to her: "Optimism is the opium of the people. A healthy atmosphere stinks of stupidity! Long live Trotsky!" It's a silly joke. But Communist party officials cannot admit it is a joke once the card is discovered or they will be branded as Trotskyite traitors too. So they make him to do forced labour in the mines.
The danger of calling the justice system Kafkaesque or comparing democratic Britain to Stalinist Czechoslovakia is that you risk repeating the exaggerations of hysterical writers. This is a free country, after all, and the state does not send the likes of Paul Chambers to the salt mines.
In this case, the totalitarian comparison is only mildly hyperbolic, however. After his managers at the car parts business heard the police call him a "terrorist", they fired him. He moved to Northern Ireland to be close to his girlfriend and found a job working for a council.
Last week, he told his employers that his appeal would be heard this Friday and his name would be in the papers. They heard the words "bomb" and "airport" and fired him too. Because of a joke, he has a criminal record and lost two jobs. The CPS is ruining his life – for no reason.
With a bit of luck, the crown court will turn his case into a legal scandal. The CPS's claim that a person's intent does not matter when they tweet a joke strikes me as false in law. More pertinently, anyone who reads the reports of the original trial can guess that the police eventually dismissed the affair as a nonsense. If so, was the defence told?
Beyond the law lies the politics. The hounding of Paul Chambers stinks of Labour authoritarianism. The prosecuting authorities showed no respect for free speech. They could not take a joke. They carried on prosecuting Chambers even when they knew he was harmless. They turned a trifle into a crime because a conviction helped them hit performance targets. Inside their bureaucratic hierarchies, it was dangerous to speak out against a superior's stupidity. Better to let an injustice take place than risk a black mark against your name.
If the court condemns the CPS, I can guarantee that Keir Starmer, the director of public prosecutions, will not fire or discipline the prosecutors involved. I doubt if he will even tell them they have undermined support for the anti-terrorist cause.
I don't care what the polls say or how unpopular the coalition becomes – Labour must change the settled view of the majority of Britons that it is the party of politically correct jobsworths or it will never win another election.
