Torture is absolutely unacceptable. This is a simple sentence but not an easy one. It is the policy of the British government, regardless of which party is in office. British agents and armed forces are not allowed to torture anyone. When some of them do, they are usually ordered to stop.

Some British soldiers in Iraq, especially in the months immediately after the invasion in March 2003, mistreated detainees. They were told to stop hooding prisoners in May 2004 but, as we report today, the practice continued in some cases. There have been several prosecutions of soldiers for abusing detainees, including Baha Mousa, the case first reported by The Independent on Sunday in January 2004. And yet, more than a decade later, we are still reporting new cases. Today, we report that 600 new claims relating to Iraq are being sent to the Service Prosecuting Authority.

If this has taken a long time, it is taking even longer to get near the truth about the culpability of the British government for torture carried out by the agents of other countries. The Senate Intelligence Committee report on the CIA's record of torture published last week in Washington exposed how far we still have to go.

When the Americans started to go after the perpetrators of 9/11, British ministers were categorical that our intelligence services should not only eschew torture themselves but also should have nothing to do with torture carried out by others. They would not use intelligence obtained by torture, so they would not "create a demand" for it. They would not tolerate it or turn a blind eye to it.

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It did not take long, however, for reports to surface that the CIA was shipping suspects around the world, using airports and bases of allied nations, to be interrogated either by Americans using "enhanced" techniques that seemed to amount to torture, or by other countries even less scrupulous about international law.

Jack Straw, the former foreign secretary, said in December 2005: "Unless we all start to believe in conspiracy theories and that the officials are lying, that I am lying, that behind this there is some kind of secret state which is in league with some dark forces in the United States … There is simply no truth in the claims that the United Kingdom has been involved in rendition full stop, because we never have been."

Such categorical assurances turned out to be unfounded, possibly because officials failed to spell out to ministers what was going on. Sometimes it may have been that ministers were not told, or that they failed to ask the right questions, which is reprehensible enough. But in at least one case Mr Straw took a decision to hand over a prisoner to the Libyan government and, reportedly, had to be reminded of it by MI6 officers after denying it to the media.

The only defence of the former government is that, unlike the Bush administration, it never explicitly authorised torture or tried to pretend that things that were plainly torture were not. But the prohibition of torture is absolute. The UK government seems to have done everything short of explicitly authorising it, and has consistently failed to be open about it.