Tony Blair's best hope is to blame the underlings and let Mr Hoon hang

Tony Blair is innocent. That is what Alastair Campbell, back in No 10 to take charge of spinning the Hutton report had the Downing Street briefers tell the Sunday press. Once such an eminent legal and moral authority has pronounced, that is surely the end of the matter; Lord Hutton's own efforts are now redundant. Indeed, Mr Campbell would have us believe that on Wednesday, the PM will go on the offensive and demand that Michael Howard retract the allegation that he lied over weapons of mass destruction.

So did Mr Blair lie? It all depends on what you mean by "lie". There is no reason to doubt Mr Blair's sincerity over Saddam's WMD. Like many other politicians and commentators - this one included - the PM believed that Saddam possessed something which was nasty and menacing. Why else would he have gone to such lengths to frustrate the UN inspectors?

Mr Blair assumed that at the very least, the invading forces would find a few rusting canisters which had contained some polysyllabic chemical. No one might ever have heard of it, but it could plausibly be represented as a dire threat. If any ungrateful persons then asked awkward questions about a 45-minute threat to the UK, they could be brushed aside. Victory and a few discoveries would provide enough political cover.

Equally, Mr Blair's statements on Iraq's WMD did not contradict the original Joint Intelligence Committee report on which they were supposed to be based; there was no attempt to turn black into white. But there was wholesale exaggeration. The "mights'', "possiblies'' and "subjunctives'' were eliminated, as all the scrupulously nuanced shades of grey in the original JIC text were painted over with lurid black, to turn it into black propaganda. David Kelly did not say that the JIC report had been sexed up. That was Andrew Gilligan's term. It was nonetheless a fair description of what had happened.

Yet again, however, the Government would have got away with it if something had been found. Any WMD material, even in small quantities, would have come close to solving the Prime Minister's political problems. He was expecting such a discovery. So did Mr Blair lie?

Well, if he had been an estate agent or an antique dealer and had employed the techniques which No 10 used on the JIC material, he could undoubtedly have been sued. If he had been a city financier, and had used such methods on a share prospectus, he would have been in danger of prosecution and imprisonment.

Even if the Prime Minister did not tell a direct lie on WMD, he did everything but. There was a word for that: prevarication. A prevaricator is someone who tries to conceal the truth without telling an actual lie. This is what Tony Blair did repeatedly and deliberately. One of the roots of "prevaricate'' is the Latin word varus, meaning bent. That is Tony Blair on WMD: not quite a liar, but serially bent.

Shortly after Dr Kelly's death, however, the PM went beyond prevarication. He told journalists he had nothing to do with leaking Dr Kelly's name. We now know, from Sir Kevin Tebbit, the Permanent Secretary at the Ministry of Defence, that Tony Blair chaired meetings at which the tactics for releasing Dr Kelly's name were discussed. When that did happen, by a process of controlled leak, nothing was done that had not been approved by No 10. When Tony Blair denied any role, he was lying.

It was an unnecessary lie. It could easily be argued that the Government was entitled to put Dr Kelly's name in the public domain. Those who deal in controversial briefings cannot automatically claim the protection of anonymity, and there was no reason to suppose that Dr Kelly would react to exposure in the way he did. If Mr Blair had admitted his part in the disclosure, he would have come in for heavy criticism, but he could have defended himself. As it is, he has discovered the truth of one of the iron laws of recent political history: that the cover up is worse than the crime.

It may be that he will escape Lord Hutton's censure for his lie, because it took place after Dr Kelly's death. Much will depend on how his lordship interprets his remit. But even if the report is silent on the matter, the stain on the PM's reputation will prove indelible.

At No 10, they are still scrubbing hard to efface it with Alastair Campbell as washerwoman-in-chief. They have also lined up a ministerial sacrifice: Geoff Hoon. No one in government cares about his reputation. On television the other day, Peter Hain could not even be bothered to pretend to support him. Poor, hapless Hoon: over the past few months, his ministerial life must have been a hideous embarrassment. His officials would still have been calling him Secretary of State, as they discussed future plans for defence policy. They and he must have known that this was all a charade. As soon as Lord Hutton published, Mr Hoon would be gone.

The Blairites are trying to ensure that he goes quietly. At regular intervals, whilst keeping their muscles tensed so as to maintain a straight face, they have been patting him on the shoulder and reassuring him that he will be alright; Tony will look after him. Surely he is not naive enough to believe that?

Mr Hoon has a choice. He could end his ministerial career, as Downing Street hopes, with scarcely a whimper, behaving like an ancient, balding, incontinent moggy going peaceably on a final trip to the vet. He could then take lessons from Peter Mandelson on how to curry favour and remind the Prime Minister of his existence. Or he could, at last, show some flourish of fight and assert himself for once in his career.

It is unlikely that he will do so. Geoff Hoon has spent so long on Blairite message that he now has a poodle's soul and a pager-text brain. That explains why up to now, no one has taken him seriously as a politician and a minister. If he now does what the Blairites tell him, no one ever will. Mr Hoon has a last chance to recover some self-respect with a defiant resignation speech.

But Geoff Hoon's fate should not distract us from the principal malefactors. In all his misdeeds, Mr Hoon was only obeying orders. That is not a defence. He should not have acted like an awe-struck lackey. He was supposed to be a Minister of the Crown. Yet justice will not have been done, unless those who issued the orders are also punished. This means Tony Blair.

Everything Geoff Hoon did wrong he did at his master's behest. The same is true of Alastair Campbell and Jonathan Powell. Though Messrs Campbell, Hoon and Powell may not have received the PM's explicit instructions on every point, there was no need. They knew what he wanted. They operated the regime that he had created. If any of them is guilty, so is he.

At the Nuremberg trials Albert Speer escaped the gallows because he had charm, sounded contrite and spoke eloquently. His deputy Fritz Sauckel, possessed none of those qualities. He was hanged. Tony Blair must now be hoping that punishing the deputies more severely than their bosses has become a precedent.