Rules for a vote of confidence may be changed if Duncan Smith stays

The Current Tory leadership rules could be radically changed if Iain Duncan Smith survives the plot against him this week, The Independent has learnt.

Senior party figures have disclosed that the current system, which was devised under William Hague and which allows a vote of confidence in the leader if only 15 per cent of MPs want one, is likely to be reviewed because it leads to damaging instability.

The crisis facing Mr Duncan Smith from his own colleagues has exposed the flaws in the procedures, and many MPs, donors and voluntary party officials have complained that the rules are "barmy" or "a recipe for intrigue". Any change in the rules would need consensus among the party's board, MPs and chairmen.

Sir Michael Spicer, the chairman of the backbench 1922 Committee, must call a vote of confidence if he receives letters from 15 per cent of the parliamentary party ­ meaning just 25 MPs need to write.

Mr Duncan Smith must win the support of a bare majority of the parliamentary party, 83 MPs, to survive. Many have pointed out that the system builds instability into the parliamentary party by giving a handful of MPs a chance to demand a vote of confidence at any time.

Worse still for any leader is the "ticking time-bomb" nature of the rules, namely that the 25 names needed for a vote remain active until they are withdrawn by the MPs concerned.

As a result, even if only 20 names are handed to Sir Michael this week, another blunder by Mr Duncan Smith would enable a further five critics to force a vote. "Almost everyone agrees that the rules need to be changed. That doesn't mean removing the right of the parliamentary party to challenge the leader but it does mean getting rid of the barmier aspects of the current system," one MP said yesterday.

A rule change could involve giving MPs a certain time period, say two weeks, at a set point in the parliamentary year in which to hand in letters. The letters could also automatically cease to be active in the process after one month.

Yesterday, Mr Duncan Smith made clear that he would seek to win a vote of confidence if 25 names materialised this week.

"Equally, if the 25 names are not forthcoming, I will expect my party to call a halt to this most damaging episode. Of course, I cannot compel the plotters to quit the field. But I am confident that my parliamentary colleagues, our party members and all fair-minded people will insist that my detractors accept that their game is over," he said. The party should resolve the current uncertainty over his position in an "honourable, honest and open way", he said.

"I want Wednesday's meeting to be a historic event. If, as I expect, no vote of confidence has been called, then there, together as a party, we can draw a line under this whole affair."

Mr Duncan Smith's aides said last night that they expected the media to turn on the plotters if they failed to get the required 25 names by tomorrow night's meeting of the 1922 Committee. One aide said: "You guys should realise that you can't trust people who keep saying every day they will have enough numbers 'tomorrow'. How many 'tomorrows' are they allowed?" Another senior Central Office source said: "Turning things round will take time but it can be done and, if the names don't appear this week, we hope that will signal a new start among both the media and MPs."

But one of the rebel MPs, Crispin Blunt, said last night that Mr Duncan Smith's arbitrary deadline would not end the crisis. "There can't be closure until it is formally closed," he told the BBC. "And it can only be closed if he gets a formal vote of confidence. It means his position can't be opened up for a year. Then, of course, that is so close to a general election a change is unthinkable."

Oliver Letwin, the shadow Home Secretary, ruled himself out of any leadership contest. Mr Letwin said he would "under no circumstances ever" run for leadership of the party.