David Cameron has apparently said that the coalition government may suffer a ‘car crash’ over an impending decision to retain the control order regime which the Liberal Democrats were pledged to abolish and on which his own party promised a review of the ‘morally objectionable and costly’ system. Control orders are in effect a system of house arrest; they severely restrict the liberty of the detainees and their immediate families and are imposed after hearings in which the accused are denied full knowledge of the secret evidence against them.  The government refuses to prosecute, using the evidence available from the intelligence services, on grounds of secrecy.

Home Secretary Theresa May is expected to announce a decision to retain control orders this week. Lord Macdonald, the former Director of Public Prosecutions, who headed the review of counter terrorism laws, is said to be strongly opposed to retention; and prominent Lib Dems, including the minister Chris Huhne, have publicly signalled their continuing opposition to the system. In an interview with the BBC, David Davis warned that 25 Lib Dem and 25 Tory MPs could rebel should the government decide to retain the "out-of-control" orders. There is also to be a decision on the fate of the power to hold terrorist suspects for 28 days without charge, which Lib Dems have argued should be rolled back to 14 days.

The potential row over control orders has an extraordinarily significant resonance. The system itself is inefficient, discredited and has always involved only a few people, currently 12 men and their families, though the effect on them is disproportionately severe. Overall just 45 men have been detained under control orders since they were introduced in 2005 as an alternative to the unlawful detention without trial of terrorist suspects from abroad who could not be returned to their countries of origin where they were likely to be tortured.  Nine detainees since have been of British origin.

The potential U-turn over abolition is a testament to the enduring power of the Home Office bureaucracy – a permanent reactionary force in British government, made more malignant by the removal of justice to the new Justice Department.  Jonathan Evans, director general of M15, has also exercised considerable influence, publicly warning in September that the government could not ‘absolve itself of the responsibility to protect its citizens’. On the right, too, the Centre for Social Cohesion (a remarkably inaccurate choice of name) has weighed in with a major report arguing against reform. No doubt the recent scare over the vulnerability of air freight to terrorist bombs has strengthened their hand.

Control orders are a human rights excrescence. The regime violates Articles 5 (the right to liberty) and 6 (the right to a fair trial) of the European Convention on Human Rights.  It is applied with vicious relish by the officials who oversee it, as Victoria Brittain’s research has shown, on isolated and deeply traumatised men, women and children, men who are frequently mentally ill.  The courts have reined in the impact of the original provisions in a series of judgments which so far have, in effect, legitimised a very British form of house arrest.  The latest ruling that detainees must be given an ‘irreducible measure’ of information in their trial suggests that the system is not sustainable in the long run whatever decision Theresa May comes to.

Just how much, anyway, do these shameful orders add to our security?  They apply to very few men, some of whom are scarcely capable of activity of any kind.  Seven have absconded since 2005 to little fuss from the authorities. The government has lifted control orders on two men rather than give more information on the case against them. Again, little fuss.  Yet the quality of criminal justice and personal liberty in Britain is utterly compromised by this nasty little system.

The Lib Dems must press their case even if they cause a car crash!