WMD and the fatal war of misinformation

The inquiry exposed Britain's intelligence agencies to their closest public scrutiny in modern times, but the judge is not expected to decide what for many is the most crucial question of the Iraq war: why was their information on weapons of mass destruction so wrong?

Although Lord Hutton heard ample evidence of the unreliability of the September 2002 dossier on Iraq's weapons of mass destruction, nothing in his terms of reference obliges him to comment on the quality of the intelligence that went into the document. He did not call for further papers or witness testimony on this point - but that does not mean he will be silent on other shortcomings within the world of spies.

The most likely target of any criticism is John Scarlett, head of the Joint Intelligence Committee (JIC), the highest clearing body for secret information. Though he told the inquiry that "ownership" of the dossier was his, he worked closely on its production with Alastair Campbell, then Downing Street Director of Communications.

Memos and emails handed over to the inquiry showed a barrage of comments by Downing Street officials on successive drafts of the dossier; they also disclosed that Mr Scarlett adopted a number of changes, proposed by Mr Campbell, which had the effect of hardening the language of the document.

Most damagingly, it emerged that the JIC chief, in response to a memo from Jonathan Powell, No 10 Chief of Staff, made a late and crucial change to the dossier without consulting other members of the committee. This removed the qualification that Iraq might use WMD only if attacked.

The inquiry also learnt that disquiet about the dossier among senior analysts in the Defence Intelligence Staff, including Dr David Kelly, never reached the JIC. Dismissed in Whitehall as minor complaints, they exploded in public when Dr Kelly talked to Andrew Gilligan, the BBC journalist. Martin Howard, Deputy Chief of Defence Intelligence and a member of the JIC, may face criticism for failing to act on the objections or pass them on.

The claim that caused most dissent was that Iraq could deploy chemical or biological weapons within 45 minutes (although Mr Gilligan later admitted he should not have said the Government knew it was wrong when it went into the dossier). The head of MI6, Sir Richard Dearlove, told Lord Hutton that he stood by the intelligence, although it referred to battlefield munitions rather than long-range weapons. "With the benefit of hindsight", he agreed it had been given undue prominence.

Sir Richard praised both the "integrity" of the dossier and Mr Scarlett's role in producing it, but at least two previous chairmen of the JIC have criticised the incumbent for having fallen under the spell of Downing Street. Lord Hutton may agree. Apart from scuppering Mr Scarlett's hopes of succeeding Sir Richard as head of MI6 this summer - his deputy, Nigel Inkster, is now expected to take over - one outcome of the inquiry could be a downgrading of the JIC. Instead of taking a leading role in assessing intelligence, it might revert to a "lowest common denominator" approach, passing on to the Government only what is agreed by all the spy agencies around the table. The JIC might also be headed by someone from outside the intelligence community, as it was in the recent past - one candidate being suggested is Lord Hutton himself.