Choosing party leaders

By: Alys Thomas


This is a blog about the constitutional issues at stake when it comes to the self-selecting memberships of political parties choosing party leaders and thus Prime Ministers.[1]

As this blog is being drafted, there is some speculation about another Conservative leadership challenge following internal disagreements over the Government’s Rwanda policy. Were it to happen, this would be the fifth time a sitting Prime Minister has been replaced without an election taking place since Theresa May became Prime Minister after David Cameron’s resignation in 2016. Although, two early elections were held in 2016 and 2019 after new leaders were in place.

Of course, this is not unprecedented, and it is not confined to the Conservative Party. The last Labour Prime Minister, Gordon Brown, took over from Tony Blair in 2007, three years before the next General Election in 2010. However, the frequency of these transitions and short lengths of terms are notable over the last seven years. Theresa May and Boris Johnson lasted three years apiece. There is talk of a challenge to Rishi Sunak although he has been in place just a year; and Liz Truss lasted just 49 days, outlived by a lettuce. While this is constitutional, as described below, it does lay bare the fact that all these changes have taken place on the say so of just one party, which in turn places some strain on our notions of democracy.

The constitutional position of the Prime Minister

The constitutional position is set out in the Cabinet Manual, a guide to the laws, conventions, and rules on the operation of government. It describes the Prime Minister as the head of the Government who holds that position by virtue of his or her ability to command the confidence of the House of Commons, which in turn commands the confidence of the electorate, as expressed through a General Election. The Prime Minister’s unique position of authority also comes from support in the House of Commons, and by modern convention, the Prime Minister always sits in the House of Commons. The Prime Minister will normally be the accepted leader of the political party which commands a majority of the House of Commons. 

The Prime Minister in turn accepts office at a private audience with the Sovereign, at which time the appointment takes effect. Where a Prime Minister chooses to resign from his or her individual position at a time when his or her administration has an overall majority in the House of Commons, it is for the party or parties in Government to identify who can be chosen as the successor.

Electing Party Leaders

It is only since the 1990s that the leadership of the Conservative Party has been decided by a vote of party members. Prior to this, leaders were elected by MPs alone, that is Heath, Thatcher, Major, Hague, and Howard. Before that, Conservative leaders used to emerge courtesy of “soundings.” Sir Alec Douglas Home was the last to become leader this way, also renouncing his peerage in order to comply with the convention that the Prime Minister should sit in the Commons (a by-election was held in West Perthshire and Kinross).

As it currently stands, the rules for the election of a Conservative party leader are set by the 1922 Committee and are not in the public domain. It usually consists of two stages: 

  • Stage 1 – Conservative MPs pledge their support to candidates and assuming no consensus emerges, the number of candidates is whittled down to two before these to go forward to Stage 2.
  • Stage 2 – Party members are a balloted, and the candidate with the most votes is declared winner.

For a vote of no confidence to be held in a sitting leader, 15% of Conservative MPs must write to the Chair of the 1922 Committee calling for a vote of no confidence. The current threshold is equivalent to 54 MPs. 

The Labour Party similarly has a two-stage process for changing leader but there are key differences from the Conservative process:

  • Stage 1 – Candidates seeking to enter the leadership ballot must be an MP and they must be nominated by 20% of fellow Labour MPs.[2] To progress, candidates must also be nominated by 5% of Constituency Labour Parties or at least three affiliates of the Labour Party (at least two must be trade unions) where the combined membership of nominating affiliates should be at least 5% of affiliated membership. Affiliates are groups or organisations which have interests consistent with those of the Labour Party – they include trade unions, and co-operative and socialist societies.
  • Stage 2 – Eligible members of the Party and affiliates vote for the leader using a preferential voting system. Each voter has one vote but may rank the candidates in order of preference by marking their ballot 1, 2, 3, etc. The first candidate to secure over 50% of the vote, using rounds of transfers of preferences if required, wins. If a candidate wins over 50% on first preference votes no transfers are required.

Labour MPs cannot formally hold a vote of confidence in the leader. However, they may initiate a leadership challenge each year prior to the annual session of Party conference. An MP wishing to challenge an incumbent leader must be supported by 20% of Labour MPs. If enough support is gathered to initiate a stage two membership ballot, the incumbent leader is automatically on the ballot paper, and they do not need to seek nominations from MPs.

Elections for the deputy leader of the party follow the same format.

Compatibility with Parliamentary Democracy

While extending the vote for party leaders to the membership can seem superficially democratic, it can be argued that it can lead to a clash with core principles of parliamentary democracy, and the ability to maintain stable government. The parliamentary system requires for the government to retain the confidence of the House of Commons. That, in turn, requires the leader of the government to retain the confidence of their own party’s MPs. However, systems involving members outside parliament risks undermining this balance. As soon as there is more than one group involved in picking the leader, there is a danger that different groups will favour different candidates. It also raises questions about the extent the which local MPs are influenced by party members rather than using their own judgement as parliamentarians.

Another criticism is that a leader imposed on MPs against their will is unlikely to be a credible Prime Minister, due to an inability to command the confidence of the House of Commons, and will thus lack legitimacy. Liz Truss’s brief incumbency is illustrative of this. In the initial parliamentary stages of the Conservative contest, she won relatively limited support. In the first round she attracted just 50 MP votes, against Rishi Sunak’s 88. In the final round, she won 113, narrowly overtaking Penny Mordaunt on 105, while Sunak stood on 137. Hence Truss had demonstrable support from fewer than a third of party MPs. Sunak and Truss were then put to a member ballot, which she went on to win by 57 per cent to 43 per cent. Her ability to push through a legislative programme was impeded from the offset, and a lack of support among Conservative MPs doubles hastened her demise. 

With regard to the last year’s multiple Conservative leadership elections, there were also concerns about the consistency of the rules for the elections and also security issues to the extent that the National Cyber Security Centre informed the party that this process left open the possibility for hackers to use the online aspect of the system to change thousands of members votes at the very end of the contest.

It can also be argued that that a party’s membership is not representative of the electorate as a whole. Last year, Bronwen Maddox wrote:

There are currently fewer than 200,000 Conservative party members and compared with the population as a whole, they are older, whiter and living in the south. The cry goes up: why should such a tiny band of unrepresentative people pick the next Prime Minister? There is inevitably pressure on the Prime Minister chosen in this way to establish legitimacy quickly through calling a general election, as Johnson did in 2019.

While the arguments advocating a stricter adherence to the principle parliamentarians deciding party leaders who go on to be Prime Minister are of valuable, in my opinion a return to such a system is unlikely. The genie of party members voting for leaders is well and truly out of the bottle and will not be returned. The challenge is for greater transparency and perhaps an expectation that a newly elected leader should seek a mandate at the earliest opportunity, not at a time that suits them.

The Fordham Judgement

Just last week a High Court Ruling was published relating to the Conservative leadership election process. Tortoise Media sought a Judicial Review of the Conservative Party’s conduct of that election on the grounds that, although the Party is a private organisation, it serves a public function when running an election that chooses the Prime Minister.  

Justice Fordham rejected the argument, ruling that the Conservative Party was not subject to Judicial Review because the Prime Minister is appointed by the sovereign on the advice of the outgoing Prime Minister, and because the new PM can then be voted out by MPs.  

However, he recognised that in practice this means the public has no means of knowing who chooses a Prime Minister mid-term and whether the election is safe or fair. This, he recognised, is arguably a failure of information rights in the UK. He further suggested that parliament might look to take responsibility for oversight of party elections leading to the appointment of a new Prime Minister mid-term, to ensure the public has a means of knowing who chooses the Prime Minister and how the process is run.

The Conservative Party’s argument, which the judge upheld, was that as a private members’ association its leadership election process is also private and one in which the court has no right to intervene. It would appear then, that for the time being, party members will continue to be able to select UK Prime Ministers. It remains to be seen whether Parliament will act on the recommendation that it develop an oversight role for mid-term transfers of power.

Alys Thomas. 

Alys Thomas has researched and written about constitutional issues for many years, particularly on the devolution settlement in Wales. From 2003 to 2019 she worked for National Assembly for Wales’ Research Service in the Constitution Team. She is a contributing writer for the Constitution Society. 

The Constitution Society is committed to the promotion of informed debate and is politically impartial. Any views expressed in this article are the personal views of the author and not those of The Constitution Society.

[1] The focus of this blogpost in Westminster. However, First Ministers in the devolved nations have changed is similar ways. Hamza Yousaf was elected SNP leader and became First Minister after Nicola Sturgeon’s resignation earlier this year; and only days ago Mark Drakeford announced his resignation as Labour leader in Wales.

[2] The current rules were last changed in 2021 when the Labour Party Conference agreed to raise the threshold for nominations from 10% to 20% of MPs.