Will the 1922 Committee change the rules tonight to allow new vote of confidence in Boris Johnson?

The 1922 Committee - the organising body for Conservative MPs - faces a momentous decision on Wednesday night.If its members believe the mood of their colleagues is that the prime minister must face an immediate further test of his popularity, following the Chris Pincher debacle and the serial resignations from government, they could allow a further vote of confidence in the PM.But the threshold for such a vote would be massively increased, to avoid the charge that the committee was somehow on a vendetta against the PM and was trampling on the party's internal rules of democracy.

The new trigger for a vote of confidence would be that the chair of the '22 committee, Sir Graham Brady, would have to receive letters of no confidence equivalent to a simple majority of MPs.

To state the obvious, if more than half of MPs wrote such letters, it would be obvious that the PM had lost the argument, so it would be tricky for him to say that a new vote was deeply unfair. The existing rules say there should be no further vote of confidence until next June, with the threshold for such a vote just 15% of Tory MPs.Such an emergency change in the rules of the '22 Committee is being actively canvassed and discussed by Conservative MPs, such is the gravity of the crisis they fear they face.The point is that unless they make that change at their meeting on Wednesday night, it is more-or-less impossible for the parliamentary stages of a leadership contest to be completed before Parliament rises for the summer in a fortnight.

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So for those MPs who want Boris Johnson to be forced out now, tonight's 1922 meeting is their last hope.What is more likely to happen however is that the '22 Committee, under the leadership of Sir Graham Brady, will launch new elections to the committee, which would take place next Wednesday. And then that new committee could change the leadership election rules the following Wednesday.But with MPs going on their holidays the following day, the PM could be confident of keeping his job at least through the summer recess.So tonight's '22 meeting will decide if the PM is at risk of being evicted in the coming few days, or whether his moment of truth will be deferred till the autumn.

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