WHISPER it softly, but the charm of the sofa style of government is starting to wear off for senior civil servants. That is the revealing implication of the latest batch of leaked e-mails in the New Statesman about the Terrorism Bill.

Power is seductive, for civil servants as much as for politicians. There is a narrow line between loyally supporting the government of the day and becoming part of the political team. When do energy and commitment become cheerleading? This is more complicated than the common charge of politicisation. There are few cases of civil servants becoming partisan in the party sense. More common is when officials become too identified with ministers, and too eager to please.

A blurring of the lines between the two has been one of the main downsides of the informal style of the Blair Government. It is much harder to maintain detachment and independence as an adviser if you are sitting on a sofa chatting informally, rather than sitting across a table at a formally minuted meeting. That is reinforced by the excitement of being an insider, particularly at No 10.

This provides much of the explanation of what went wrong over the use of intelligence before the Iraq war, as was made clear by the July 2004 report of the inquiry led by Lord Butler of Brockwell. It was not just that the raw intelligence was not subject to full scrutiny and analysis. As important was that Sir Richard Dearlove, then head of MI6, became part of the inner group around Mr Blair. He was blamed by many in the intelligence world for not being sufficiently detached from the Blair inner group.

John Scarlett, his successor as head of MI6, and then chairman of the Joint Intelligence Committee, is seen by insiders as trying to maintain the integrity of the committee’s analysis. But he did agree to the publication of the September 2002 dossier, which distorted the available intelligence.

There are signs, however, that Mr Scarlett has learnt the lesson that the intelligence agencies should not allow themselves to be used to make an essentially political case. According to the memos in the New Statesman about the proposed banning of some Islamic political groups, an official reported that the agencies “do not oppose proscription but oppose reliance on their assessment to justify what they see as a change of policy, not fact”. Mr Scarlett is reported as saying that he “sees this as a political issue and a matter for the Foreign Secretary”.

Similarly, MI5 refused to be enlisted, and cited, as part of the public argument for the proposed 90-day detention of suspected terrorists, which was defeated in the Commons in November. It was wary of the proposal and of being dragged into the political debate.

Greater detachment is desirable. The agencies should be held accountable: for problems such as their assessment before July 7, as well as for successes such as the still largely unappreciated role of MI6 in the dismantling of Libya’s weapons of mass destruction programme. But it is up to politicians to make the case for changes in law on their own.

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