No confidence motion will give redress to MPs

Mr Duncan Smith appears powerless to haul Mr Blair to the Commons to answer these allegations

After the Commons has listened to Tony Blair's likely obfuscation on weapons of mass destruction during Question Time later this morning, the next item of parliamentary business ought to be a motion of no confidence in the Government - or, at least, in the Prime Minister.

When one former cabinet minister alleges that Tony Blair has been "duping us all along" and another former cabinet minister - once the Foreign Secretary - accuses the Government of a "monumental blunder" then the charge against both the Government and the Prime Minister is just about as serious as it can get. Indeed, according to the Labour MP, Malcolm Savidge, the issue ranks with the Watergate affair.

Politics is littered with such accusations but they normally come from a government's political opponents. What makes these charges so damning is that they come from two of the longest-serving members of Mr Blair's government, formed more than six years ago. Robin Cook sat at this cabinet table until 10 weeks ago and Clare Short was there until just 22 days ago.

But the only person who can normally table a motion of no confidence in Mr Blair, under the usual parliamentary convention, is the Leader of the Opposition. The question is whether Iain Duncan Smith is too embarrassed to do such a thing after he has been standing "shoulder to shoulder" with the Prime Minister. But if Ms Short was trapped, so surely was the Tory leader - especially by those fulsome tributes from Mr Blair about not making political capital.

Mr Cook and Ms Short resigned not just over the usual political bread and butter issues. They resigned over the Government's decision to go to war with another sovereign country which, it was claimed, posed a threat to our national security. Their initial decisions to resign could be explained away by the requirements of our system of collective responsibility. Mr Cook was not prepared to serve from the moment such a decision had been taken. He was certainly not "duped" and always believed the conflict was wrong.

Ms Short was persuaded to hang on for as long as it suited the Prime Minister and the messy nature of her initial threat to leave, which she did not carry through until hostilities were over, compromised the eventual impact of her resignation. But she defended her decision to stay on the basis of certain assurances given to her by Mr Blair. We now learn from Ms Short that we were "duped all along" and that we were "misled" and "deceived".

Notwithstanding the charge of naivety which could be levelled at Ms Short, especially by those MPs such as Mr Cook who were certainly not duped and who could see all along that this war was wrong, she is, nevertheless, making even more serious accusations.

In this sense, Ms Short's comments makes it imperative for those MPs on all sides, who voted in the same lobby as Mr Blair, to be at the forefront of the process of calling the Prime Minister and his Government to account. The accusation is that Mr Blair secured his mandate from MPs for war by being dishonest.

We now see how useless the democratic process of accountability becomes when both main parties are in agreement. Much is made of the new vogue of supporting the Government "when we believe it is right". Mr Duncan Smith appears now to be powerless to haul Mr Blair to the Commons to answer these exceptionally serious accusations because of his prior enthusiastic support in the debates before and during the conflict. But it cannot be right for Ms Short's claim of prime ministerial duplicity to be left hanging in the air. It would be a cruel irony if the only person standing on the sidelines, while Labour MPs call into question the honesty and integrity of the Prime Minister, is the Tory leader.

The worst option would be some kind of "independent inquiry" - or even a parliamentary inquiry, both of which are bound to be some kind of fix or whitewash. Talk that Downing Street is already conceding the possibility of involving the Security and Intelligence Select Committee - under the chairmanship of Tony Blair's former chief whip, Ann Taylor, fills me with horror. As Kenneth Clarke has rightly acknowledged, this is a matter that needs to be resolved solely by all MPs - collectively - on the floor of the House.

Thankfully, Michael Howard, the shadow Chancellor, speaking on Radio 4's The Westminster Hour has acknowledged that there is a question over whether the Government told the truth in the run up to the war, and "whether the government did try to dupe the people, to cook its case, to doctor the intelligence and that's a very important question which goes to the heart of the integrity of our government".

If it turned out to be the case that the Government engaged in deception in order to gain public support or get the support of the Labour Party for this war, he said, "that would be an immensely serious matter going to the very heart of the integrity of our government." On this basis it ought to be possible for Mr Howard and his frontbench colleagues to argue that they were similarly duped for their support.

Only a motion of no confidence will give redress to MPs who must be feeling pretty sick at being arm-twisted into the lobby on a false basis. But just as Mr Blair cannot ultimately escape his constitutional responsibilities, neither can Mr Duncan Smith.

mrbrown@pimlico.freeserve.co.uk