How would a leadership contest in the Conservative Party work?

Published: 19th Sep 2018

There have been recent reports that Theresa May might face a leadership challenge from Conservative MPs. But how might that happen?

We haven’t seen primary copies of the Conservative Party’s constitution, but the rules have been reported by the House of Commons Library.

How can a leadership contest can be triggered in the Conservative Party?

There are two ways this can happen. Either the leader resigns, or loses a vote of no confidence.

For a vote of no confidence to take place, 15% of Conservative MPs have to express that they have no confidence in the leader. This is done by writing a letter to Sir Graham Brady MP, chairman of the 1922 Committee—a committee of all backbench Conservative MPs which, among other things, oversees the party’s leadership elections.

As there are currently 315 Conservative party MPs, this means that 48 would have to say they no longer have confidence in Theresa May.

The number of letters submitted so far isn’t publicly available—one rumour suggests it could be at least 35, but there’s no way for us to know for sure.

What happens after a vote of no confidence is triggered?

The 48 letters are enough to trigger a vote of no confidence, but the leader is only deposed if they lose the ensuing vote.

All Conservative MPs get one vote (in favour of or against the leader staying on), and the leader stays on if they win a simple majority of the votes. In such a scenario, 12 months would have to go by before another no confidence vote could be called.

Were they to lose the vote, the party leader would have to resign and a leadership election would be triggered. The resigning leader can’t stand in that election. The winner would become the new leader of the Conservative party and, as they are currently in government, also Prime Minister of the UK.

Why can’t parliament hold such a vote?

It can, but it has to vote on whether it has confidence in the whole government, not just the Prime Minister.

In order to do so the House of Commons would have to propose and vote in favour of a motion stating “That this House has no confidence in Her Majesty’s Government”. Following this, there would be a 14 day period in which to form a new government, based on the existing make-up of MPs. The House of Commons would then have to vote to say they now had confidence in the new government. Were this to fail, a general election would be triggered.


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