David Lipsey: Let the public decide on PR

The safer the MP's seat, the greater the likelihood they will be cooking the books

The late Roy Jenkins had one aim above all for his 1998 report on electoral reform: that, unlike so many other well-argued theses for changing Britain's failed first-past-the-post electoral system, his report should not remain unread mouldering on the political shelf. But accumulate mould it did. Labour MPs, in the pomp of their electoral hegemony, said "no" to Jenkins, and so did the initiator of the Jenkins report, Tony Blair. It was generally proclaimed deceased, and Lord Jenkins died in 2003 a disappointed man.

Well, there must be joy in heaven right now. A whole decade later, Roy's report (and it is rightly described as that though I, Baroness Gould, Sir John Chilcott and the late Lord Alexander signed it too) has suddenly burst back not as a theoretical treatise but as a practical proposition with every chance of prevailing. Alan Johnson, practical politician par excellence, has endorsed it; Nick Clegg, for the Lib Dems, has joined suit and indeed it now seems that in every party except the Tories there is a wave of enthusiasm for Jenkins.

Having bashed my head against a brick wall for many years as chair of Make Votes Count, a pressure group campaigning for Jenkins, I am astonished but not surprised. I am astonished because political corpses rarely rise and walk. I am not surprised because in politics, crises can suddenly redraw the art of the possible. As politics sinks into the political mire in the wake of the expenses scandals, the Jenkins proposals are suddenly being seen as a serviceable life raft.

Electoral reform on the Jenkins model would precisely address the present problems. Jenkins's first major change was to propose the alternative vote (AV) for constituency MPs. Voters would list constituency candidates in order of preference. Those with the fewest votes would be eliminated and their votes would be transferred to stronger candidates until one candidate had 50 per cent plus one votes.

This would give voters a direct opportunity to punish the minority of expenses-fiddlers. For at the moment, an MP has every chance of clinging on to his or her seat with as little as a third of the vote: in other words, two-thirds of voters can vote for the sack yet the MP survives. Under the AV system, any MP who does not command the support of a majority of constituents is out.

There is some evidence that the safer an MP's seat is, the greater the likelihood they will be cooking the books. AV reverses this. Most MPs would be in peril if they had to get at least 50 per cent of the vote, and so most MPs will have the strongest possible incentive to avoid fiddling.

Electing MPs solely by constituency has another defect: it leads to parties winning majorities even when they are backed by only a minority of voters. Again, this means parties have to work harder to get overall majorities, and therefore have a greater incentive to behave well. And it makes it easier (though still not easy) for new parties – Greens, independents and who-knows-what groupings to come – to establish a foothold at Westminster. Again, the hand of electoral retribution is strengthened and improved MP behaviour is the likely result. In this it differs from some of the other remedies being sought by reformers. Each has its merits; but none has anything to do with fixing the present crisis.

Reduce the power of the prime minister and increase that of parliament – as David Cameron pledges? A grand idea, but the public might think that MPs have shown themselves worthy of less power, not more. Elect the House of Lords – as Nick Clegg proposes? Well, election hardly served to keep our MPs on the straight and narrow, and it is hard to brand the Lords venial when its members work without salaries. Fixed-term parliaments? – but what difference to the present crisis would have been made if the date of an election was determined by law, not by the prime minister?

The intellectual case for Jenkins is powerful; the political case that it actually helps to lance the boil equally so. Alas, that does not mean it is bound to happen. There are various practical obstacles but the main one is the opposition of the Conservative Party. Under David Cameron, the party has abandoned most of its beliefs in search of office but there are two exceptions: anti-Europeanism, and an unchanged voting system.

One solution to this is to adopt the first half of the Jenkins solution, the AV, straight away. A bill to this effect would certainly pass the Commons with Lib Dem and most Labour support. It should survive Tory opposition in the House of Lords. For surely even their lordships would not seek to stand in the way of a measure that would so clearly increase the power of the electorate to decide which individuals deserved to represent them in the new parliament.

So far as the top-up, to increase proportionality is concerned, that is a bigger change, and naturally more contentious. It is vain to think Mr Cameron would endorse it now. But what Mr Cameron might be forced to endorse is the idea that it would be the subject of a referendum. He says he wants to increase voter power. Well, then, let him give voters power to decide which electoral system they want. He is, of course, entitled to try to defend the present system during that referendum campaign, which would not come earlier than the general election. What he is not entitled to do is to continue to take the moral high ground on voter empowerment while denying them the right to decide. I may mistake my man, but I do not think he would wish to imperil his chances of power by taking such an anti-democratic stance.

The writer is a Labour peer and a member of the 1998 Jenkins report on electoral reform