Blunkett has admitted guilt over his travel expenses, but so far there is no evidence of full-strength corruption

The worst argument for saying that David Blunkett should resign is that his private life has become such an object of public interest that he cannot fulfil the duties of his great office of state. One sub-argument is that he is so distracted by affairs of the heart that he cannot give his full attention to affairs of state. A second sub-argument is that he has shown such poor judgement in his domestic arrangements that he cannot be trusted to make the right decisions about the nation's future. And a third is that the hullabaloo in the media makes it impossible for the Home Secretary to get on with his job, or that it somehow undermines the credibility of the Government as a whole.

The worst argument for saying that David Blunkett should resign is that his private life has become such an object of public interest that he cannot fulfil the duties of his great office of state. One sub-argument is that he is so distracted by affairs of the heart that he cannot give his full attention to affairs of state. A second sub-argument is that he has shown such poor judgement in his domestic arrangements that he cannot be trusted to make the right decisions about the nation's future. And a third is that the hullabaloo in the media makes it impossible for the Home Secretary to get on with his job, or that it somehow undermines the credibility of the Government as a whole.

All of these arguments are weak, and the third is particularly hypocritical. It is as disreputable as the argument - which no one could deploy in public - that we do not like his illiberal policies on asylum seekers or identity cards so we are going to use his love life to bring him down.

The question is whether - as Home Secretary - Blunkett has done anything seriously wrong. So far, he has definitely done one thing wrong, but it is not serious enough, in my opinion, to justify his resignation. He has admitted breaking the rules on travel expenses by giving Kimberly Fortier, now Quinn, a warrant, reported to be worth £180. This is not a trivial offence. In many lines of work, an employee might be in danger of losing their job for fraudulently claiming that amount of money from their employer.

Blunkett offered two linked excuses in his defence: that he thought of Kimberly as his spouse and that he had not examined the "detailed rules". Neither is impressive. Ignorance is no defence and the rules say: "You will be asked for the names of your spouse and children, so that we can provide books of warrants." Sir Philip Mawer, the Parliamentary Commissioner for Standards, will produce his verdict in due course and no doubt Blunkett will make a formal apology in the House of Commons, having repaid the money. If that is all there is, that is where the matter should rest.

Some Conservative journalists, witchfinders general of the moralising inquisition, will accuse anyone who reaches this conclusion of being soft on New Labour. They say that, far from politicians being required to abide by a higher standard of ethical conduct than ordinary mortals, they are given an easy ride by sympathetic columnists. I hope this is not true. If Michael Howard had given a travel warrant to someone who was not entitled to it, with no suggestion of corruption, I would like to think that this column would be explaining why he should resist opportunistic Labour demands for his resignation.

Blunkett's survival in office, therefore, ought to depend on whether it can be shown that he has done anything else wrong. Hence the interest in Sir Alan Budd's inquiry into the allegation that the Home Secretary speeded up the grant- ing of the right of UK residence for the Quinns' nanny. Once again, the media-political complex has been in full hypocritical overdrive. The Prime Minister was criticised for pre-empting the inquiry by saying that he had "no doubt" Blunkett would be exonerated. What was Tony Blair supposed to say? That he thought the Home Secretary had been up to no good but he wasn't sure? And was Sir Alan supposed to think, on hearing the Prime Minister's words, "Oh, so the PM wants me to exonerate him? Scrap that first draft then."

At the same time, the media has hyper-ventilated the Conservative complaint that Sir Alan's inquiry isn't independent enough and/or broad enough. Which is just another way of pre-empting it by assuming that it will come up with the wrong result. To which the obvious response is to wait and see. If Sir Alan's report is patently unsatisfactory, then the Conservatives can make their case. As it is, it is unclear what further allegations the inquiry should have been broadened to cover.

The Conservative frustration is understandable, however, because Blunkett is likely to be cleared. I say this not because Sir Alan is a craven lackey of the Thatcherite New Labour neoconservative neoliberal elite, but because Blunkett himself was so emphatic that he had done nothing wrong and so quick to ask for an arm's-length inquiry. He strikes me as a man who is very sure that there is nothing incriminating in the paper trail.

However, his spokesman has changed his story about the visa, saying initially: "Kimberly asked David Blunkett for his advice on whether the application was in good order. He said it was. It did not go through his office." Later, he admitted: "David took it with him to the Home Office", and that his principal private secretary or his deputy "may well have read it to him and looked it over".

If Blunkett did show the application to his civil servants, that would be another misdemeanour. It cannot be right for a minister to allow his officials to know of his personal interest in a case, for fear that they might give it preferential treatment even if they are not asked to do so.

But that might not be a sacking offence either. It would rank worse in the league table of work-related misconduct than using the office telephone to vote in I'm A Celebrity. But it is hardly full-strength corruption. After all, Peter Mandelson was "exonerated" after the event by the Hammond inquiry into the Hinduja passport affair. That was on the curious grounds that speeding up the Hindujas' applications was justified because it would save civil servants from having to respond to the representations of "prominent people".

Meanwhile, other allegations against Blunkett seem to have fallen away. The first suggestion of impropriety that was thrown up by the turmoil in his private life, and which was partly used to justify reporting it, was that the Home Secretary had phoned the US embassy to speed up a passport for Kimberly's son. But the press has lost interest in that because there is no reason why a father should not inquire about his (presumed) son's passport. If the US authorities want to give preferential treatment to a leading British politician, that is a matter for them.

The remaining charge is that Blunkett has used his access to the press, which he enjoys only because he is Home Secretary, to pursue a private battle. Again, if true, it would not be edifying but, again, not a sacking offence - unless it involves the abuse of public money or civil servants.

The case against David Blunkett is not proven and not likely to be proven. If people disapprove of his policies, they should argue against them. If people have opinions about the conduct of his private life, they are entitled, within limits, to express them, because he has taken his dispute with Kimberly Quinn to the courts - a public arena and, in last week's case, fully and rightly public despite the family courts usually being shrouded in secrecy. But as Home Secretary he has done nothing to require his departure. He should stay.