At the last roll of the dice, sanity has lost out to legal dogma. The Government's long-drawn-out battle to deport suspected foreign terrorists is effectively over. Yesterday's two judgments by the Court of Appeal make it extremely unlikely that Britain will ever manage to deport Abu Qatada and other foreign terror suspects, a point tacitly acknowledged by the Home Office's decision to drop its attempts to deport a further ten Libyans in addition to the two whose appeals were successful yesterday.

These people came in through Britain's leaky borders and were allowed to stay, in some cases, because of wilful sloppiness by the immigration authorities. Now our human rights laws mean that we are stuck with them. We cannot keep them under arrest much longer after these rulings. So they will soon be free to wreak what havoc they will.

Abu Qatada, a radical Muslim cleric described as al-Qaeda's “ambassador in Europe”, is wanted in Jordan, where he has already been convicted of terrorism offences. Last year the Special Immigration Appeals Commission ruled that he could be deported to Jordan because he was not at risk of torture there. But the Court of Appeal does not agree. It is concerned about torture at one remove. If Abu Qatada were to face another trial in Jordan, the judges have ruled, that trial might involve evidence that might have been obtained under torture. The court's decision turns on the possibility of a possibility of a possibility. In the case of the two Libyans, the appeal judges have confirmed that they are a threat to national security, with links to al-Qaeda. But they are worried about the treatment that these extreme Islamist opponents of the Gaddafi regime would receive in Libya.

The rulings are a blow to ministers who have spent two years securing diplomatic assurances with Jordan, Libya and Lebanon that deportees would not be ill-treated. But the Government's hopes that it could neutralise its own Human Rights Act in that way were always going to be disappointed, because those assurances are unenforceable. It was surreal to think that we could ever trust such regimes not to ill-treat people. The question should be: do we need to trust them? If Britain wants to deport foreigners whom it considers a threat to national security, should it feel responsible for what kind of treatment they get elsewhere? And if we do feel some responsibility, then how much?

In one sense, you can see why the judges put the potential safety of UK citizens second to the safety of terror suspects. Article 3 of the European Convention on Human Rights (ECHR) prohibits torture, inhuman or degrading treatment or punishment. The people who wrote that convention were scarred by the atrocities of the Second World War. That sobering thought must hang over sensible discussion of this issue.

But politicians cannot simply abandon their duty to protect the public. So those who incorporated the ECHR into British law in 1998 (and congratulated themselves loudly on their deftness in drafting the Human Rights Act) put parliamentary sovereignty on a direct collision course with the judiciary. The result has not been cost-free in terms of human rights. Britain should never have given Abu Qatada refugee status in 1993, after he claimed asylum on false papers. But by the time the Home Office woke up to the danger, it dared not risk challenging Article 3. Instead it suspended habeas corpus, which for 400 years has been a fundamental guarantee of liberty in this country, and put Abu Qatada and others into Belmarsh prison without charge. Was leaving them in a no man's land, without trial in any country, really better than sending them home to face justice?

After three years, the Law Lords rightly ruled that Belmarsh was something akin to a British Guantanamo Bay. Ministers put the suspects under control orders instead - which the judges also challenged. The dance moved on to the “memos of understanding” signed with countries suspected of torture. The Government asked Amnesty International to monitor whether those countries complied. Amnesty refused. We are now back to square one. Our constitution is bruised, the independence of our judiciary has been challenged, some of the men who were under control orders have absconded and our European allies are incredulous.

The Government intends to appeal against the latest rulings. But there is only one court left: the House of Lords. The Home Office said yesterday that Abu Qatada would remain in prison. But for how much longer? He can only be held for as long as there is a “realistic prospect of deportation”.

Is there a way out? There are two. One would be to bring charges against such men, and abide by the result of a fair trial. The Government lacks the stomach for that - and apparently the evidence, which ministers need to explain better, given the accusations made. The other would be for Britain to do in principle what other countries, such as France and Spain, have done in practice - derogate from the ECHR. Lawyers will say this cannot be done, because Article 3 is an “absolute prohibition”. But we have tied ourselves up in legal knots. At the moment, the ECHR takes precedence over the 1951 Geneva Convention (which gives countries a right to return any refugee who can reasonably be regarded as a danger to society). That cannot be right. The Geneva Convention is hardly a charter for fascism.

Torture is a nasty business. So is internment. But so is terrorism. There are no easy choices - yet choices have to be made.

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