David Blunkett has betrayed the trust of all those who care about civil liberties

In a frenzy, he targets and harasses specific individuals, declaring that he will 'nail' one particular thug

Let's imagine a Tory government ten years from now. The Home Secretary prides himself on being a hard man. He announces he is considering charging victims of miscarriages of justice "for their bed and board for the time they were in jail." The next Birmingham Six would be handed a bill for their accommodation in Pentonville as they emerged from their cells.

Let's imagine a Tory government ten years from now. The Home Secretary prides himself on being a hard man. He announces he is considering charging victims of miscarriages of justice "for their bed and board for the time they were in jail." The next Birmingham Six would be handed a bill for their accommodation in Pentonville as they emerged from their cells.

He withdraws this policy, but laughs at the "Hampstead liberals" and "civil libertarian know-nothings" who protested. He proceeds to reintroduce internment, jailing a dozen Muslim men indefinitely without any public charges or trial. He dismisses those who oppose this as "not taking terrorism seriously". In a frenzy, he begins to target and harass specific individuals who he suspects of "causing trouble", declaring that he will somehow "nail" one particular petty thug.

We're there. David Blunkett has done all this. The accusation that the current government is a spin-obsessed bunch of right-wingers is a lazy lie - except in one instance.

Yesterday, as Blunkett announced plans for a national police database in the wake of the Soham inquiry, the Home Affairs Select Committee went to inspect the scene of one of Blunkett's greatest crimes. Twelve Muslim men are being held indefinitely in Belmarsh Prison. They are boxed into small cells for 22 hours a day. Their offence? They don't know, and nor do you. Under the Prevention of Terrorism Act 2000, even their lawyers have no right to be told why they are being detained. After two years, there are no plans to charge them with any crime.

This is not punishment, it is judicial kidnapping. The canon of Western law - built upon habeas corpus - was designed to prevent precisely this arbitrary exercise of power. Blunkett sneers that only residents of NW3 would worry about such trivia.

The Home Secretary seems to have genuinely missed the point of civil liberties. B ensuring that the police and politicians are not just rounding up the usual suspects, proper judicial process actually makes everyone safer. When the Guildford Four and the Birmingham Six were jailed, it wasn't only their lives that were ruined; real terrorists were left free to carry on murdering - and there are graveyards full of innocent people who can vouch for it. Blunkett's plan for constricting civil liberties is based on a trade-off - liberty for security - that does not work in reality.

The last time civil liberties were attacked in this way - in the 1970s and early 1980s - a long stain of miscarriages of justice occurred, and the terror threat only worsened. It will happen again. Soon there will be a Muslim Hugh Callaghan and a hijab-wearing Carole Richardson. Helena Kennedy, the Labour peer, has described the contortions which have led a Labour government to this. "Decent ministers intent on outflanking the right become the right, moving so successfully into that political space that they lose their political as well as their moral compass," she explains.

Blunkett claims that it is a very different set of political circumstances that have brought him to this point. He says that Britain faces a unique threat in the form of al-Qa'ida, a jihadist death cult determined to maximise civilian casualties. In the light of this new danger, dusty notions of civil liberties must be torched. Habeas corpus is not a suicide pact.

He is right about the nature of al-Qa'ida. But the individuals being held at Belmarsh can hardly be mini-Bin Ladens, because Blunkett has announced that he will happily release them to any country that would be prepared to take them. If we had really dangerous terrorists in our hands, would we make such a pledge? With his give-away offer, Blunkett has surely all but admitted he is currently suspending basic freedoms to detain relatively minor individuals.

Kennedy, in her important recent book, Just Law, answers Blunkett's self-justificatory retort, "Well, what would you do instead?". The Swedish government recently confronted the dilemma Blunkett also faces: they hosted a terror cell against whom they had evidence that could not be admitted in court - either because it came from a mole or from phone taps, which cannot be admitted as evidence in their courts.

"The Swedish government decided," she explains, "their legal system was too precious for them to depart from. They arrested suspects and sought to question them; when met with silence, they released them but have kept them under constant surveillance ever since. The suspects know they are being watched and having their calls intercepted 24 hours a day."

This is uncomfortable for civil libertarians, but in extreme cases justifiable; the suspects can continue - subject to periodic judicial monitoring - being watched until either there is enough evidence to try them, or they seem to have renounced their terrorist sympathies. Why has Blunkett so casually dismissed the Swedish option for a dozen terrorists, opting instead for the Guantanamo approach?

The Home Secretary's willingness to proceed on the basis that he "knows" a suspect is guilty - without due process having been followed - spilled this week beyond terror suspects. His declaration that he will "nail" Garry Mann assumes the alleged hooligan is guilty, even though Mann was convicted in a couple of days in Portugal in a fast-track court and his case is under appeal. Proper translation services were not made available to him, and there now seems to be CCTV footage showing him to have been nowhere near the scene of the crime.

It is predictable that Blunkett's disregard for hard evidence in terror cases would spill into other areas. The erosion of civil liberties in Britain has often followed this pattern. The right to silence was snuffed out in Northern Ireland in 1988, although the government protested this was a response to an extreme threat, and would be temporary and strictly confined to the province. In 1994, the right was removed for all British people. We may never get it back.

Blunkett's contempt for civil liberties means that even when some tougher measures are sensible, he cannot be trusted to enforce them. As Sir Michael Bichard's report into the Soham murders made clear yesterday, a national police database might help to prevent paedophiles getting jobs in schools. But who can have faith that Blunkett will put in place safeguards to ensure the system is not abused by the police or employers? A national identity card could be useful too; but who wants Blunkett in charge of their biometric data?

And what about in the worst case scenario of all - a terror attack? Terrorism presents two jagged dangers. There is the harm terrorists can do to us, which we saw illustrated on the streets of New York and Madrid; and there is the harm terrorists can make us do to ourselves out of fear and panic.

What would David Blunkett - willed on by a terrified public - do after our own 11 September? If an attack is, as the Government assures us, "inevitable", shouldn't the Prime Minister get a reasoned politician into place in the Home Office now?

j.hari@independent.co.uk