John Rentoul: You should have gone, John

The BBC is losing the disciplines of public service broadcasting

John Prescott should have gone ages ago. Two years ago would have been a good time, for example. Tony Blair could have been ruthless after his deputy prescotted on about the tectonic plates moving in May 2004. To prescott is a verb with which we have now become familiar, meaning to talk apparent gibberish while using words for a precise and calculated purpose. On that occasion, the purpose was to try to nudge the Prime Minister out of the exit door that Blair had told Gordon Brown - in Prescott's presence - that he would use, but which he was pulling shut again. Last week, Prescott's calculated purpose, in an interview on the Today programme, was to save himself from being pushed out of another door farther down the corridor of power.

If Blair had deprived him of his department two years ago, that would have cleared the way for a dignified exit from the Government after last year's election. Then there would have been little interest in his affair with Tracey Temple, which had already been in progress for 18 months. There would have been no croquet on the lawn of Dorneywood. And there would have been no stay last year at the ranch of Philip Anschutz, the American plutocrat who took over the Dome.

The election for deputy Labour leader that so grips the speculators of Westminster might already have taken place. The most enjoyable part of Prescott's interview on Thursday came when he realised that John Humphrys did not know what the Labour Party rules were. "The trouble with you, John, you read too many papers." he said. "If you want me to read out the constitution I will do. If I resigned now there doesn't have to be an election, no. So you're quite wrong." He kept this up for the last two minutes to stop Humphrys asking any more questions about his private life.

Technically, Prescott was right, as confirmed by the highest authority in such matters, Mr Alan Watkins, on page 35. A deputy leadership election is in fact specifically ruled out in the party rules - "until the next party conference". Not many people know this, as Prescott so gleefully discovered.

The party's rules have long been a secret garden guarded jealously by officials who know that information is power. Although not all officials went as far as Margaret McDonagh, general secretary in the early Blair years. She once told the party's National Executive that no more than four contemporary motions could be tabled at annual conference. Liz Davies, the hard-left member who was disqualified as a parliamentary candidate, produced the rule book and said there was nothing of that kind in it. To which McDonagh replied: "Some rules are not written down."

More than a vestige of McDonaghism lingers at the heart of the party's apparatus. The rule book is on the internet, but only behind a members-only firewall on the party's website. The rules that govern not just what would happen if Prescott resigned, but the transition from Blair to a new prime minister, are regarded as the private property of members rather than as matters in which every citizen has an interest.

Ultimately, however, all rules are subject to politics. If Prescott resigned, there would be an election soon enough. And, fun though it would be to see Alan Johnson win, it is unlikely to happen because an election is not in the interests of Blair, Gordon Brown or the Labour Party. Leadership elections are an opportunity to advertise renewal; deputy leadership elections are a way to advertise internal division.

The Ministerial Code is subject to politics too. Prescott's stay at Philip Anschutz's ranch was a clear breach of the code, which instructs ministers to "avoid accepting any gift or hospitality which might, or might reasonably appear to, compromise their judgement or place them under an improper obligation". But the seriousness of the breach, and the punishment therefore, are decided by the Prime Minister. He told MPs last week that he would take action if he thought there was reason to: "But I am not going to do that every time someone makes an allegation". No, he is only going to do that when politics dictates that he has to. As it did last year when David Blunkett broke the code, arguably on a procedural point of lesser importance (he had failed to "seek advice" from the advisory committee on business appointments). But Blunkett was dispensable; Prescott's ability to force a party election makes it riskier for Blair to sack him.

Prescott is certainly throwing everything on to the fire to keep the media wolves at bay. A donation to charity in lieu of the price of a hotel was an attempt to blow smoke in our eyes. It hardly mitigates the breach of the code, and we still do not know when the donation was made. The suspicion must be that it was after The Times asked Prescott about the ranch visit. I am also told that Prescott's press officer did not return The Times's call for three days, until 6pm on the Friday before England's quarter-final against Portugal. It was an attempt to muffle the story by giving The Times little time to write it for a day when the nation's attention was elsewhere. A late entry in the Register of Members' Interests was another confused attempt to limit the damage - more like admission of guilt and a plea for clemency.

In this situation, with Prescott on the Today programme fighting for his political life, only one person could save him. John Humphrys rose to the occasion magnificently. By asking Prescott whether he had had other affairs, he forfeited the ground on which a case could be made against the Deputy Prime Minister in the public interest. It was evidence of a BBC out of control, not in the sense that it is corporately trying to do the Government down, but that it is losing a sense of the disciplines of public-service broadcasting. When Prescott asked why the question was justified, Humphrys replied: "Because I wanted to give you the opportunity to clear it up." If that is the BBC's test of the public interest when invading someone's privacy, the licence-payer is entitled to an explanation of the new policy.

It would have been better for the country and for Prescott himself if he had bowed out gracefully two years ago. But he didn't. And now it is essential, for the sake of the principle that even politicians are entitled to a private life, that he sacrifice the last shreds of his reputation by staying.