Voting Systems: Which One is Best?

 by James Heppell

When you go to vote in the UK, you vote for 1 candidate, belonging to the party you like, who represents your local area, and you’d be forgiven for thinking that’s how it works everywhere in the world. But in fact there are 14 different systems in use today, and many hundreds of variations. In this article I’ll talk you through some of the most common. Which one is the best you ask? Well, that depends who you ask. For my money though, I think STV is the best system out there. 

1. First Past the Post

First Past the Post is the voting system the UK currently uses for its general elections. It's used in quite a lot of other countries, mostly former UK colonies, such as the US (which uses a variation) and India.

The UK is split up into many hundreds of constituencies of roughly equal size (~70 000 people on average). When you vote at elections you vote for your local representative. You get 1 vote, and aren’t allowed to order the candidates. The candidate with the most votes wins and becomes the member of Parliament for your constituency.

The main advantage of FPTP is that it's very easy to count votes, and everyone has a local representative they can talk to. The main disadvantage is that seats are not  completely representative of votes, especially for smaller, non-regional parties.

Seats vs Votes 2019 General election without Conservatives or Labour. Regional parties (eg Scottish national party) do quite well.

2. Party list proportional representation

Party list proportional representation is perhaps the most used voting system in the world, largely used in Europe, South America and parts of Africa, and is used when the UK holds elections for the European parliament.

  

Red = FPTP, Blue = PL-PR, Green = STV, Purple = MMP. Pink = Parallel voting. Marron = TWo Round System. Original map

In PL-PR you vote for a party instead of, or as well as, a candidate. Constituencies are much bigger than in FPTP (~25 candidates), and in some cases (e.g. Netherlands) may be the whole country. Seats are awarded directly proportional to votes, and individual candidates can be chosen by parties (closed list) or voted on at election day (open list).

The main advantage of PL-PR, is in the name: it’s as representative as it’s possible to get. The % of the vote you get is the % of the seats you get. The main disadvantage is that you may not get a local representative, and if you do they won’t actually be that local, as constituencies are such big areas in this system. PL-PR can often lead to coalitions in power, as big parties don’t get over-represented, which can be both a good and a bad thing (more views taken into account, more disagreement).

3. Single Transferable Vote

Single transferable vote is a fairly uncommon system, used by Ireland, Malta and in local elections across the UK (N.I, Scotland, Wales). It aims to combine the proportionality of PL-PR with the local representation of FPTP, all while giving voters more choice. A big claim. 

In STV constituencies can have anywhere from 3 seats upwards. The more seats the more proportional, but the less local candidates are and the harder it is to count votes. Generally 6 strikes a good balance, and 3/4 is not recommended because of how hard it is for small parties to get seats. 

Hampshire constituencies FPTP system

In an STV election you order all of the candidates. If your 1st choice is knocked out, your vote gets transferred to your second choice, and so on (see video below). This has two main advantages: one is you can choose between different candidates within parties, and another is you can support small parties which you might not otherwise vote for because you think they’re unlikely to win so your vote would be wasted (tactical voting). MPs are less local, though you are more likely to have one who’s from a party you support. The main disadvantage of STV is how complicated it is. Sure, computers can do most of the counting now, but it still takes a lot longer than FPTP and is harder for vote counters and voters to understand. 

Example STV election (A visualisation makes it much easier to understand)

Hampshire constituencies STV system

4. Mixed Member Proportional / Additional Member System

While more common than STV, MMP is still a quite uncommon system, used in Germany & New Zealand among other places.

While STV aims to combine FPTP with PL-PR, Mixed Member Proportional literally does. Half of the MPs are elected via a FPTP election, the other half of the MPs are assigned to parties based in order to make them have the same proportion of seats for votes. For example if I got 2 seats through FPTP, and you got 1, but we got roughly the same amount of votes (eg 51% to 49%), 1 seat would be awarded to me through PR, and 2 to you. Usually both the elections happen at the same time, on the ballot paper you would vote for a candidate and a party.

The main benefit of this is seats are awarded proportionally, and you still get a local candidate. The disadvantage is that it’s, again, more complicated than FPTP.

Some more voting systems briefly

5. Parallel voting

Parallel voting is similar to MMP, but different in that PR seats are awarded to make the PR section of the seats proportional, rather than awarded to make all seats proportional to the PR vote. Eg in parallel voting if I got 10% of the PR vote, but got awarded 0% of the seats in the FPTP vote, I’d be given 10% of the PR seats, 5% of the seats in total. In MMP I’d be awarded 20% of the PR seats, to give me 10% of the total seats. Russia, South Korea and Japan use this system. 

6. Instant runoff voting / Alternate vote

AV is the same as FPTP, but you order your candidates. Lowest candidates are knocked out, and their votes transferred until a candidate has > 50% of the votes, in which case they win that seat. Australia uses this method and we had a referendum on whether to adopt it in 2011.

7. Two round system

Two round system is FPTP, but with two rounds. After the first round all candidates but 2 are knocked out.