David Cameron’s announcement that he wouldn’t serve a third term makes the front pages of most of the newspapers today, and on Buzzfeed Lib Dem Secretary of State Vince Cable has heaped scorn on former party president Tim Farron’s leadership ambitions.

Whatever the outcome of the general election at least one, and very possibly two, of the three main party leaders will be making way for a successor. Each of the three parties has different rules for electing leaders, and those rules will shape the nature and the outcome of any leadership elections. In that context, we thought it would be useful to provide an overview of the rules for each of the three main parties.


The Tories’ process for picking a leader is twofold: Conservative MPs narrow the field to two choices, before a postal ballot of the wider membership of the party is conducted.

The Chairman of the 1922 Committee, which represents Conservative MPs, acts as the returning officer for leadership elections. Graham Brady is currently serving in this post. The Conservative Whip (currently Michael Gove) receives nominations from members of the House of Commons, and the deadline is noon “on a Thursday”.

If one nomination is received, the new leader is declared elected. If two nominations are made, both names go forward for the members of the party to decide between. In the event that three or more MPs are nominated for leader, a ballot of Conservative MPs is held “on the Tuesday immediately following the closing date for nominations”. The ballot is held under the first past the post system. If MPs are choosing between four or more candidates, the candidate with the lowest number of votes is eliminated and further ballots are held on subsequent Thursdays and Tuesdays until only two MPs remain.

The wider membership of the Conservative party then chooses between these two MPs, with the vote being held via a postal ballot. The returning officer chooses the date by which ballots have to be returned and the count begins at noon that day. The result is announced at a meeting of the parliamentary party and “representative members”.


The Labour Party has changed its procedures for electing its leader since the election of Ed Miliband. The next election will use the “one member one vote” (OMOV) system, where all Labour members, affiliated supporters and registered supporters shall have one vote of equal value. This marks a change from the electoral college system used in previous elections where three equally weighted blocs determined the outcome: Labour MPs and MEPs, party members, and members of trade unions and affiliated socialist societies. Under this system, Ed Miliband polled fewer votes in the MP & MEP and party membership blocs but was narrowly able to win due to the strength of his support amongst the trade unions.

In order to run for leader, an MP must be nominated by 15 per cent of the party’s sitting MPs – a small increase from the previous requirement of 12.5 per cent. As an example, the party currently has 256 MPs so an MP would need to be nominated by 39 of his or her peers to run for leader at present.

The precise timings of the process are determined by the party’s National Executive Committee, which has representatives from the parliamentary party, constituency parties, trade unions, socialist societies and party sections such as Young Labour.

Labour’s general secretary, currently Iain McNicol, acts as returning officer for the party. A legal adviser and “independent scrutineer”, both appointed by the general secretary, also play a role in the process. The election is held using AV, with voters ranking candidates in order of preference and their votes being counted and redistributed until a candidate reaches the quota of 50 per cent + 1 votes. The result is announced at a session of the party’s conference.

Liberal Democrats

The Liberal Democrats require candidates to be nominated by 200 party members representing at least 20 local parties. The party’s Federal Executive sets the timings for nominations, dispatch and receipt of ballot papers.

Similarly to Labour, the Liberal Democrats operate on the principle of OMOV, and the party also uses AV to elect its leader.


The rules for these leadership contests are important, and the outcome of any election cannot be considered without reference to the rules. In particular, the rules for the election of a Conservative leader shape the contest, with the 1922 Committee acting as a “selectorate” that limits the membership’s choice. Labour and Lib Dem aspirants face lower barriers to being presented to their parties’ memberships. Like the Conservatives, Labour MPs have a role in nominating candidates; while the Liberal Democrats have the most open nomination process, involving party members directly.

It’s likely we’ll see at least one and perhaps two of these systems springing into action shortly after the general election.