The Lib Dems abhor them but the coalition has already used the controversial anti-terror measures

Nobody pretended running a country would be easy, but at 10.22pm last Tuesday the new government would have appreciated the sharp incline of its learning curve.

The special immigration appeals commission had ruled that Abid Nasser and Ahmad Faraz Khan, both aged 23, the alleged operatives of an al-Qaida plot to bomb targets in north-west England, could not be deported to Pakistan because they risked being tortured there. Neither could they be jailed because the evidence documenting their terrorist involvement was too sensitive to be heard in open court, meaning they could not face trial. The government faced a dilemma.

As it transpired, the answer was there all along: the much unloved control order. It might have been attacked mercilessly by the Lib Dems, but last week it was sanctioned by the coalition government for the sound reasoning that there is nothing better out there.

Ostensibly, control orders are about containment of risk, a palatably termed type of house arrest in the eyes of critics, a sort of prison without bars. Introduced in 2005 a few months before the 7 July attacks on London, they are designed to stop people leading a normal life. There are currently just 11 in use. They can last indefinitely, and the longest one so far has been in force for three years.

Terrorism suspects – for that is their sole target – are given a boundary around their home that they cannot cross, often a mile, sometimes less. They are not allowed to use the internet or phones, other than the one in their home – the only address that they are allowed to use. Their passports are confiscated and they can also be banned from using buses, trains and the tube. Often they are not even allowed to leave their home, with some facing a curfew of up to 16 hours. In addition, they must check in daily with the police, who in turn can arrive at their home unannounced and confiscate or examine any object inside.

Suspects are electronically tagged and need ministerial permission for all manner of everyday events, such as visiting a place of worship, the identity and location of which must be clarified beforehand. The home secretary has the power to impose other restrictions if deemed necessary.

Unsurprisingly, control orders are not cheap – the average cost last year was £225,633 per person. But that is small change compared with the cost of defending this particular counter-terrorism initiative; the government has paid £8m in legal fees trying to fend off a near-constant barrage of challenges since it was introduced.

In 2006 a high court judge ruled control orders were incompatible with the European convention on human rights. Since then, the law lords have questioned most aspects of control orders, including the length of curfews and one of its most controversial aspects: the use of secret evidence.

Just two days before the general election the supreme court was told that control orders involving a curfew lasting 16 hours a day violate fundamental rights.

Away from the judiciary, the criticism is no less stinging. The system has been likened to an open-ended form of house arrest and criticised for its potentially damaging psychological effects, infringement of liberty and denial of fundamental rights, such as the presumption of innocence.

Given the unequivocal opposition of the Lib Dems to control orders and possible shame at having to rely on them just days into government, a full review of the system has already been announced by ministers.

History indicates that a penchant for human rights trumpeted in opposition can soon wear thin in power. New ministers can quickly find the authoritarian measures they condemned in opposition rather less noxious once installed in government.

Reconciling personal liberty and national security has proved a difficult task for Whitehall so far. It remains to be seen whether the swagger of a fresh government can buck that trend.