What makes a good voting system?
I am fascinated with voting systems. More so than any party leader or any one policy the voting system decides who governs.
Having just had local elections in the UK I wanted to examine the qualities of what makes a good voting system, the different system used and their qualities. Ultimately I hope to make a judgement on what system we should use.
The properties of a good voting system?
Proportionality: all good voting systems should be proportionate. It is self-evident that any system in which a party gaining a small minor of votes can hold a majority of seats is a poor system. It follows then that the more closely the elected body match the overall distribution of quotes the fairer it is. While there is no innate limit to the improvement of the proportionality, at not point are we going to say “that’s enough, we could improve it but we won’t”, there does come a point at which we would have to sacrifice other attributes to increase proportionality.
Locality: representatives should represent an area and area’s should have a representative. This representative should be in tune with local issues, available to their constituents and able to champion causes important to them at a higher level. As such improved locality initially looks like spreading the representatives as even as possible resulting in the smallest possible constituencies but there is a flip side. If a region has an issue it needs championing and the local representative represents a party that is opposed to that issue in general it is unlikely to be championed. Thus a balance needs to be struck. Good locality looks like the smallest number of constituents linked to their representative without leaving behind large blocks of constituents who have no-one to champion their causes.
Not that these 2 attributes work against one another. Small constituencies maximise the locality of a system, with each representative representing the fewest people. A system exclusively made up of small constituencies, however, is more likely to result in poor proportionality as each constituency will is more likely to waste votes. Example 2 constituencies of 51% Conservative 49% labour each electing 1 representative will elect 2 conservatives wasting nearly half the votes.
Voter choice, Spoilers, & honesty: voters are a broad and diverse cast of actors and yet we must select from 3 (4 in Scotland) credible parties for our MP’s the current system. This number is kept down because the current first past the post system rewards consolidation and punishes nuance. Parties that split in 2 get less seats between them than they would get combined. This forces parties and voters to think strategically, party members endure bedfellows they can barely stand in order to avoid splitting the vote, and voters must at least consider voting dishonestly. By ‘voting dishonestly’ I mean they must consider voting for some who in not their first choice but has a greater chance of getting elected. This in turn sends out a false message about the countries preferences as well as resulting in a parliament that does not accurately reflect its people. A good voting system will allow voters to vote honestly, will not penalise voters or parties for splitting a region on the political landscape and will encourage more options or positions to be made available for voters to choose from.
Safe seats & engagement: in 2017 labour won the seat of Liverpool Walton with 86% of the vote. This is disheartening for the people of that constituency. Their 1 vote had less power than any voter in any other constituency in the country. Safe seats, on the whole, are bad for the community. The cost is twofold. First no party is looking to win them over. In Walton, Labour know the seat is locked down and so to campaign on specific local issues would be a waste of resources while everyone else knows they can’t win it and so ignore it likewise. Secondly the voters themselves are disengaged. Multiple studies have shown that voters in safe seats know less about the parties and their positions and turn out in lower numbers than their counterparts in marginal seats.
Simplicity & comprehension: lastly and good voter system should chiefly be easy to vote within. The voters should be able to understand how to vote and what the impact of their vote will be. Secondary to this, voters should be able to understand how the vote is counted and the votes turned into representatives.
The main options
First past the post (FPP) - currently used for Westminster elections.
How it works
Set up: The country is divided up into constituencies, each constituency elects one representative.
How you vote: Everyone gets one vote for one candidate
How it’s counted: most votes in each constituency wins.
Example:
5 Parties run in a Constituency, A, B, C, D, & E:
The votes are distributed as follows: A-20%, B-34%, C-24%, D-16%, E-6%
Candidate B has the most and is therefore elected.
The voters for E and D would probably be disappointed with the result and if even half of them voted for C, who is more aligned with their preferences, at the next election C would win. This results in consolidation and tactical voting.
How it does:
Proportionality: FPP has terrible proportionality, the worst on this list. This is the result of two attributes. Firstly the constituencies are small and the smaller the constituencies are the worse they represent the overall sentiment as we discussed earlier. The second is that there is no need to get the support of half the constituency. Outside of England where there are 4 competitive parties this vote share can get ridiculously low. In the 1992 election the Lib Dems won the constituency of Inverness, Nairn and Lochaber with only 26% of the vote, the Conservatives in fourth place got 22.6%. Overall, in the 2019 general election there was a 17% misalignment between the votes cast and the seats won by party.
Locality: each seat is connected to the smallest possible local area, but many people don’t agree with their MP making it difficult to get their issues championed
Voter choice, Spoilers, & honesty: FPP is the system that spawned the idea of spoilers. It is terrible on this dimension massively punishing small parties, encouraging consolidation and forcing voters to think tactically not honestly.
Safe seats & engagement: while FPP can result in competitive seats it’s also resulted in some very safe ones.
Simplicity & comprehension: extremely easy to understand. There’s a single count of the vote with no fiddling about.
Alternative Vote (AV) – used in Australia.
How it works
The country is divided up into constituencies, each constituency elects 1 representative. (same as FPP)
How you vote: Everyone ranks the candidates by their preference,
How it’s counted: least popular candidates are eliminated, and their votes redistributed until someone has more than half the votes.
Example:
5 Parties run in an election, A, B, C, D, & E:
The voter’s rank the candidates in their preferred order.
The votes are distributed as follows in the first round: A-20%, B-34%, C-24%, D-16%, E-6%
As no candidate has reached 50% of the vote the lowest achieving candidate (E) is eliminated, and their votes distributed to each voters next preference:
The votes are distributed as follows in the second round: A-20%, B-34%, C-25%, D-21%
As no candidate has reached 50% of the vote in this round the lowest achieving candidate (now A) is eliminated, and their votes distributed to each voters next preference:
The votes are distributed as follows in the second round B-51%, C-28%, D-21%
As Candidate B has passed the 50% threshold they are elected.
This process allows voters to cast their first vote in line with their closest preference and does not penalise them for doing so.
How it does:
Proportionality: AV is better than FPP but it could still result in large misalignments.
Locality: the constituency construction is the same as FPP but AV is more likely to result in a representative that is available to more of their constituents and so is likely to be able to champion a larger proportion of local issues than FPP.
Voter choice, Spoilers, & honesty: as your vote is not wasted if your first choice if for a small party if solve the spoiler effect and allows people to vote honestly. However, while AV is far better for small parties than FPP it is still difficult for the smaller parties to get representation that comes close to their overall vote share.
Safe seats & engagement: as a rule, winning margins in states that use AV are smaller which should lead to less safe seats and more engagement. This is due to two pressures. Firstly, AV allows for the formation of small parties and so a safe constituency is likely to be targeted by a small party that is more extreme but in broadly the same direction as the holding party. Secondly voters still need to make a second or third choice giving them a reason to learn more about the candidates.
Simplicity & comprehension: there is no complicated maths here 1 list which you rank. The multiple rounds as some frustration but how you vote and how the representative is chosen is clear.
Mixed Member Proportional (MMP) – used in Scottish parliament, welsh assembly, Germany & New Zealand
How it works
The country is divided up into constituencies, each constituency elects one representative with 30%-50% of positions set aside for ‘List Seats’. The list seats are allocation in line with party lists so that the overall proportion of seats in the parliament as closely reflects the over vote share as possible.
How you vote: Everyone gets one vote for their constituency candidate and 1 vote for their party preference, the party they would vote for without considerations for the individual rep or how the rest of the public in their constituency will vote.
How it’s counted: the constituency votes are counted first, typically using FPP, and then additional MP’s are added from the List Seats set aside (chosen from party lists) in order to make the overall distribution of MP’s at a national level match the party preference indicated in the second vote.
Example:
5 Parties run in an election, A, B, C, D, & E.
There are 200 seats in the elected body with 100 constituency seats and 100 List Seats.
The voter’s select the candidate they want to represent them as well as voting for the party they want to represent them.
The constituency seats are allocated as follows: A-18, B-49, C-20, D-10, E-3
Next the party seats are counted with the results as follows: A-20, B-34, C-24, D-16, E-6
Seats will then be selected from party lists to get the result such that the representation of each party matches this distribution.
These list seats are distributed as follows: A-22, B-19, C-28, D-22, E-9
How it does:
Proportionality: MMP usually results in near-perfect proportionality. The only exception being when one party gets so many more constituency seats than their party votes that there are not enough list seats to balance the ratios.
Locality: locality suffers as the list seats do not represent an area meaning that the constituency seats have all the problems of FPP but also more constituents.
Voter choice, Spoilers, & honesty: MMP provides an avenue for small parties and avoiding spoilers through the party votes but this is small fry compared to other systems. The party lists also remove an element of voter choice. If you vote for a party, they chose who that vote goes to which feels like a slight divorcing of the democratic process.
Safe seats & engagement: every vote counts for the party lists, so in that way MMP is a significant step up on previous systems but it can still have safe constituency seats as well as offering back up as senior party members are often on the lists as insurance in case they lose their constituency.
Simplicity & comprehension: the initial vote is simple but the party lists are a bit of trouble. How far down the list a party gets is dependent on their nationwide performance and you as an individual are going to have difficulty know who you are voting for on the lists.
Single Transferable Vote (STV) – formerly used for the UK’s EU elections
How it works
The country is divided up into large constituencies, each constituency elects multiple representatives and each party can put forward multiple candidates.
How you vote: Everyone ranks the candidates by their preference in the same way they would for AV.
How it’s counted: the counting occurs in rounds. In each round if a new candidate passes the threshold need to be selected, they are elected and excess votes are redistributed. Otherwise, the least popular candidate is eliminated, and their votes redistributed until all seats are allocated.
Example:
5 Parties run in an election, A, B, C, D, & E. with three Parties putting forward 2 candidates for 3 positions.
The voter’s rank the candidates in their preferred order.
The proportion of votes needed to get elected is 1 divided by the number of positions +1 => 1/(3+1)=25%
The votes are distributed as follows in the first round: A1-12%, A2-8%, B1-20%, B2-14%, C1-14%, C2-10%, D-16%, E-6%
No-one has passed the 25% threshold and so the smallest (E) is eliminated and their votes redistributed. A1-12%, A2-8%, B1-22%, B2-15%, C1-14%, C2-11%, D-18%
Again, no-one has passed the 25% threshold and so the smallest (A2) is eliminated and their votes redistributed. A1-15%, B1-27%, B2-15%, C1-14%, C2-11%, D-18%
B1 has passed 25% and so is elected. The 2% of excess votes they received are distributed among the remaining candidates: A1-17%, B2-15%, C1-14%, C2-11%, D-18%
No new candidates have passed the threshold and so the smallest (C2) is eliminated and redistributed: A1-17%, B2-15%, C1-17%, D-26%
D has passed the threshold and is elected and the 1% of excess votes redistributed: A1-17%, B2-15%, C1-18%,
B2 is now eliminated as the smallest resulting in: A1-24%, C1-26%, with C1 being elected
The final results: B1, C1 & D are elected.
Note that 5 representatives is generally seen as the smallest Typically
How it does:
Proportionality: while not as proportional as MMP this is still far better than either FPP or AV.
Locality: the locality here is the opposite of all the other systems. With significantly larger constituencies it is harder for the candidates to be aware of the local issues however, with more representatives per constituency voters are more likely to have a candidate they are aligned to who can then champion their issues.
Voter choice, Spoilers, & honesty: as with AV voters can vote honestly knowing that unpopular votes won’t invalidate their choices, similarly new parties won’t act as spoilers for similar existing parties. With multiple representative’s, smaller parties are far more likely to get representation than under AV or FPP increasing voter choice.
Safe seats & engagement: there will be no entirely safe seats. Anything less than 90% vote share means that there is at least one seat in contention. As a side effect of the selection process because the voters can select which member of a party they are voting for individual party candidates are often in competition with each other. This means that some political areas may fracture into new parties or existing parties will over increased voter choice within their umbrella as candidates seek to differentiate themselves form their party colleagues.
Simplicity & comprehension: this is the only real downside of STV. While it is very simple to for voters to cast their vote it is complicated to count and explain.
Conclusions
There is no perfect voting system that gives broad choices and engages voters with perfect representation, good local links and is easy to understand but there is a clear winner in my book, Single Transferable Vote. While it is more complicated to understand than the alternatives it is really simple for voters to use, rank your choices. STV also allows for a far greater level of voter choice as it will encourage new parties and candidate differentiation with maintaining local links and ending up with good proportionality.
