How May’s London Assembly elections will work

Tara Azar, former Student Placement

Posted on the 7th April 2021

This May, millions of Londoners will go to the polls to vote for the Mayor and the London Assembly.

The London Assembly is the political body that holds the mayor to account and scrutinises their budget. The Assembly and mayoral elections take place every four years.

The London Assembly

London Assembly members are elected through the Additional Member System. This requires voters to vote once for their desired constituency member and once for a London-wide representative.

In total, there are 14 constituency members – picked by First Past the Post – and 11 London-wide members. Voters use two ballot papers, putting an X next to a constituency candidate, and an X for their party of choice for the London-wide list.

The London-wide list acts as a proportional ‘top-up’, meaning voters whose choices are unrepresented through the First Past the Post element can still have their party choice heard on the Assembly.

This leads to greater political diversity – preventing one party from unfairly dominating without a mandate from the majority of voters (as happens too often under the winner-takes-all system of First Past the Post).

If the London Assembly had been elected using solely First Past the Post, then the voters of parties other than Labour and the Conservatives would have gone completely unrepresented across the 20 years since the Assembly’s establishment.

The 2016 London Assembly election

At the last election for the London Assembly, the results were as follows:

Seats Seats % Constituency Vote % London Wide Vote %
Labour 12 48% 43.1% 40.3%
Conservative 8 32% 31.1% 29.2%
Green 2 8% 9.1% 8%
UKIP 2 8% 7.6% 6.5%
Liberal Democrats 1 4% 7.5% 6.3%
Others 0 0 1.2% 5.3%

Labour’s 43.1 percent and the Conservative’s 31.1 percent allowed them to split all the First Past the Post constituency seats between them, with Labour winning nine (64%) and the Conservatives winning five (36%).  Even though almost one in 10 Londoners voted Green, their vote was too spread out across the capital to win any constituency seats. In over 20 years, 10 of these 14 seats have never changed party control.

Thankfully the London-wide vote is designed to compensate for the effects of First Past the Post. The London-wide vote sets what the Assembly’s composition should look like at the end, that is how many seats each party should have. In 2016, Labour won 12 seats, with the first nine being taken by the nine Labour candidates who won the constituencies and the remaining three coming from an ordered list published by the party in advance of the election.

The 2021 London Assembly election

Polling by YouGov for Queen Mary University of London at the start of March 2021 has Labour up five points since the 2016 contest in the party list vote, at 45 percent. In the constituency element, the party was up three percentage points, at 47 percent.

But with Labour already over-represented in the chamber, they will find it hard to translate these gains into more seats.

‘The composition of the Assembly after the election will most likely look very similar to how it does now, albeit with slightly more Green and Lib Dem members,’ said Professor Cowley who organised the polling.

The deadline to register to vote is Monday 19th April 2021. Once registered, should you wish to vote by proxy, the proxy vote application deadline is 5pm on Tuesday 27th April.

If you want to use a postal vote instead, the application deadline is Tuesday 20th April, 5pm. If you live in London, make sure you’re registered, and make your voice heard.

This year marks 20 years of proportional representation being used for the London Assembly, a fantastic milestone.

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