It is rare to see Britain’s intelligence agencies, MI5 and MI6, in open battle with MPs from all parties, including the Deputy Prime Minister.

That is not necessarily how Britain’s spooks see it and certainly not how they want it to be seen. They point out that the row over proposed restrictions on how intelligence is used in court are principally a matter for the Ministry of Justice, which produced a Green Paper on the subject last year.

But it will be the spies whose reputation – and whose ability to share information with the Americans – which will be damaged if this row over open or closed courts is not resolved quickly. As it must be, in the interests of Britain’s national security

Let me explain. Since September the 11th, the degree of intelligence sharing between the British and Americans has reached levels not experienced since the Second World War. The Americans tell us far more than we tell them, because their intelligence apparatus is so much bigger. Whatever you think of the UK’s involvement in Iraq and Afghanistan, the most important by-product of the “Special Relationship” in the last decade has been the degree of US Intelligence which reaches here. 04 terrorblog g k Spooks do battle with MPs

But in recent years, an undercurrent of anxiety has beset the relationship. Put simply, the Americans have backed off telling us as much as they could. The trigger for this was a series of civil court cases, brought by Binyam Mohamed and other former Guantanamo Bay detainees, in which vital evidence came from the CIA. So adamant was MI6 that this information from its most important partner should not be aired in court, that the government felt itself forced into costly out-of-court settlements instead.

At risk here was the so called “Control Principle”. An Intelligence Agency reserves the right to decide how far its intelligence should be shared. And the Americans, long criticised for their interrogation techniques and their use of “extraordinary rendition”, do not want their unlawful practices or the intelligence it produced ending up in British courts. Nor, for that matter, does MI6, still recovering from the reputational damage of the Iraq war fiasco and the continuing “guilt by association” which tarnishes the image of its closeness to the CIA.

Nobody in government doubts that this relationship with the Americans is worth preserving. But at what cost to British justice? The political row is about whether ministers or judges should have the power to decide what intelligence should be disclosed.

The government’s Green Paper proposed last October that ministers should have that power. Now an all-party backlash is in full swing, after a parliamentary human rights committee said the proposals were a departure from the norms of open justice.

Civil liberties groups – and libertarians on all political parties – are arguing with the government about the way forward. One option is a Canadian-style system, whereby judges are trained in intelligence matters and are therefore more sensitive to MI5 and MI6′s concerns. Whatever happens, compromise will be the order of the day.

And in the meantime, the risk is that the intelligence tap in Washington continues to drip ever more slowly, with the Americans refusing to disclose raw intelligence material in favour of generalised threat warnings which give less information away.

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