I for one do not wish to see the tax returns of our leading politicians.London Mayor Boris Johnson started this trend, publishing his own returns in order to embarrass his opponent Ken Livingstone, whom he accuses of avoiding tax by having fees paid to him through a private company instead of directly. (Though tax avoidance, of course, is not actually a crime. In my view it's a virtue, because it gives governments less money to waste.)

Now Britain's Chancellor of the Exchequer, George Osborne, stung by accusations that his personal wealth may have influenced his Budget proposals, has offered to release his own accounts. Business Secretary Vince Cable is apparently considering the same. And pressure is mounting on party leaders, such as the Conservatives' David Cameron, the Liberal Democrats' Nick Clegg and Labour's Ed Miliband, to follow suit.

I hope they don't, though I fear that once these bandwagons start rolling, they are hard to stop. Yes, it seems all too obvious that politicians should disclose their personal circumstances to the electors, so that any vested interests they have might be exposed, and so that we can judge whether they are in fact living up to the standards they claim for themselves and are actually practising what they preach for the rest of us. But the reason I don't want politicians to disclose their accounts is that it will prevent other, ordinary people from challenging the political class, further increasing the separateness and power of that class.

Let's face it, even if we have nothing at all to hide, most of us reckon that our family finances are our affair. We really don't want other people snooping into them – not even our relatives, friends and neighbours, never mind random people in the street or journalists from News International. Most normal people see themselves as entitled to a private life. Politicians used to think so too, but now they live their lives on the front page, they have to be prepared to see any part of their lives exposed to public and media scrutiny. Which means that people do not now go into politics unless they are prepared to put up with such exposure. And most ordinary folk, as I say, are simply not prepared to put up with that. So increasingly, politics attracts a very odd class of person, and puts off anyone who is actually remotely normal. And this proposal for politicians to reveal their tax affairs just increases that political class divide even further.

Before long, other members of the political class will be caught up in this 'transparency' frenzy too. Top civil servants, quango chiefs, media editors, newspaper columnists, pressure-group leaders, public affairs consultants, corporate lobbyists and the heads of campaigning charities will all come under pressure to publish their tax returns. Good, principled and independent people will exclude themselves from these professions, rather than have their personal lives pored over. Only exhibitionists, and those for whom the thrill of power is more important than personal dignity and privacy, will apply for such jobs. The political class will get stronger, bigger, and more separate. And unchallenged by those good, principled and independent people for whom the personal price of getting involved in public life is too high.