In England, said that great Victorian constitutionalist, Walter Bagehot, “...with pains and labour - by the efforts of attorneys - by the votes of freeholders - you collect more than six hundred gentlemen” (he was talking about our House of Commons). “And the question is, what are they to do?”

So it was in Bagehot's time, and so it remains today. What are they to do? We must never try to find a final answer to that question. Seek to rationalise the role and purposes of the backbench Member of Parliament, and you will rationalise him into either a paid employee of a quasi-governmental bureaucracy, a scared messenger for whatever fad or fury grips the imagination of the mob this week, or you will rationalise him right out of existence.

And now is a dangerous climate in which to try it. Britain has gone beserk. I returned on Thursday to find my country in one of its periodic fits of moral horror. At such times, witches have been burnt, monkeys hanged as French spies and Catholics hounded out of office.

There is no arguing with a spasm of popular anger. Hitch a ride on it if you are the Leader of the Opposition; play to it if you want to boost your media profile; but the rest of us do best to duck and wait for the spasm to pass. A public mood in which Dr Ian Gibson, a decent, thoughtful, independent-minded Labour MP and one of Parliament's few trained scientists, can find himself the top story in yesterday's news because he let his daughter live in his London flat, is a public mood with which there can be no reasoning. Extravagance, genuine mistake, sly acquisitiveness and outright criminal fraud are now jumbled together in the national mind as though there were no moral differences. Judgment has fled. This is the worst possible climate in which to consider root-and-branch reform of our system of representative democracy.

I have read carefully the various proposals now canvassed for a rebalancing of the relationship between Members of Parliament and the electorate they represent. I strongly agree with this newspaper that in an ideal parliament, fewer MPs would be paid more.

I agree with The Times, too, that open candidate selection is worth promoting: the Conservative Party is already experimenting with this, and I've chaired a number of Tory candidate selections to which the non-Tory public were invited - and arrived in significant numbers. In principle an oddity, in practice the occasions seem to work.

The “recall” proposal, under which a public petition of sufficient size could trigger a by-election, troubles me. How can you define and dictate to the public (or verify) the allowed and disallowed reasons for challenging their MP? Yet if the proposal is to make the trigger depend simply on the collection of a very large number of signatures, then who are best placed to mobilise such a campaign? Rival political parties, whips' machines, party HQs, bloggers, mischievous newspapers, and single-issue lobbying groups.

Besides, do MPs necessarily serve the country best when forced to keep a weather eye out for moves to unseat them? Some of the finest parliamentarians I've encountered have taken a scornful view of the idea that their duty is to do what their constituents tell them, on a weekly basis.

For behind any list of reforms we compile stands that constitutional confusion to which Walter Bagehot's question pointed. What are MPs for? However defined, the role must surely amount to more than acting as a conduit between the desires of the voters and the policies of the government; for that logic points to abolishing MPs altogether: we have the technology today to capture accurately, daily, the desires and opinions of voters; and no modern need to funnel them through the unreliable channel of hundreds of flesh-and-blood intermediaries.

Why then do we need this assembly? To choose ministers from? There are surely better ways of assembling a ministerial workforce. To serve their constituents through MPs' surgeries, then? This cannot be a Member's primary purpose; they are not trained or qualified to be citizens' advice bureaux; they trespass on the work of more appropriate officers; and they jump queues for the sharper-elbowed among their constituents.

MPs' surgeries can only be justified by what they teach MPs themselves about the needs of the citizens and the pinch-points (and successes) of public service delivery.

But if MPs are to be educated, what are they being educated for? And back we come again to Bagehot's question. Plainly an assembly of some 650 men and women cannot in any meaningful way occupy the cockpit of government. There isn't room. The easy thing to say is “to hold the government to account”. But few MPs have the skills to do this in the expert and methodical way that modern government requires. The press sometimes do it better. In asking the right questions the clerks to the select committees could beat most of their Members into a cocked hat.

I'll tell you when, in my view over three decades, MPs as an assembly have seemed to me to be functioning best. It's a largely negative function. It's when the House as a body, or a significant current of feeling within it, is roused to anger, anxiety, indignation or despair at what an administration is doing. It's in its ability to harry, chivvy, wreck and rebel, to grumble, drag its feet and trip its masters up - and, just occasionally, to roar its leaders on - that the House as a gathering of real people comes alive.

They can't do it all the time, or government would be impossible. They must listen to the voters much of the time or democracy would fail. Their party whips must command for most of the time or programmes for government would be a charade. But without a certain self-regard, without a fair number of idle hands for the Devil to find work for, without a little vanity and a lot of confidence, without an uneasy struggle, never resolved, between conscience, constituency and whip, the irksome, tiresome, bothersome, troubled thing that the British House of Commons can so valuably be, will not survive.

Give them a kicking, Times readers, when they deserve it. Some of them now do. But don't kick all the stuffing out of them. Don't give them so savage a kicking that, when Government needs a kicking, there is nobody left who is able to kick.

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