Friday, May 07, 2010

Keeping it in proportion

It looks like the Tories are going to try to cobble together some sort of minority government, maybe with some Lib Dems on board - although Cameron's 'big, open, comprehensive offer' didn't seem to amount to much - so we may miss out on a Proportional Representation deal between Labour and the Libs. This is a massive shame, and it's a massive shame for Labour as well as the Liberals.

Labour has traditionally supported First Past The Post, because they've believed that it works for them and they can form strong governments in their turn. But the reality is that since 1997 FPTP enabled Labour to betray a lot of their supporters - to take them for granted - in pursuit of the middle ground of middle England. So electoral reform could in theory allow a truly progressive coalition to govern, marginalising the Tories and the right-wing centre of gravity that has held the country in its grasp since the 1980s.

Maybe it's wishful thinking. I don't know where the idea that the UK has a progressive majority actually comes from, but I think it's certainly true that the changes wrought by a new electoral system will be far more far reaching than just empowering the Liberals to hold the balance of power. It is likely that it would dramatically change both the two major parties profoundly. Which is what we supposedly want isn't it?

This is the day after the election that never (sort of) was, and I'm not doing very much. So with my sense of public service geed up from watching all those selfless politicians at work, and because I think someone might possibly find it helpful, I hereby present:

criticalbill's guide to electoral systems

I've tried to keep it as plain as possible. Despite being mostly culled from wikipedia, I'm confident that it's relatively accurate, or at least I will be once someone who knows about these things has had a good look over it. It is of course another missive from the politics-student-who-never-was, but what can you do.

Labour is, at the moment, offering the Lib Dems the Alternative Vote Plus system, which is the one that the Jenkins Commission recommended for the UK in 1998 and which the likes of Brown and Straw put the kibosh on then. The Lib Dems would really like the Single Transferable Vote system. There are other possibilities as well but I'm going to ignore them.

Some electoral systems are divided into single-winner systems and multiple-winner systems, ie. some elect one winner per seat, others elect a pool of winners. Some electoral systems allow voters to choose between individual candidates, others allow voters to chose between parties, who then allocate candidates from a 'party list' to fill the vacancies. Party list systems do not favour 'maverick' representatives, and instead concentrate power in the party hierarchies.

The First Past The Post system that the UK uses has several advantages:
  • It is easy to understand.
  • It provides a direct link between an elected member and a particular constituency area, ie. Mr Bloggs is the member for Bollocktown.
  • It tends to give clear results, with artificially-strengthened governments, ie. although no party has polled over 50% for many years, we have had a succession of governments with majorities in the Commons, allowing them to govern effectively. This is not necessarily an advantage, but it is promoted as one.
FPTP has some disadvantages:
  • A huge number - more than 50% - of votes are technically 'wasted', ie. it wouldn't have mattered if most people hadn't bothered to turn up, since once one person is elected, all the other votes are thrown away.
  • The final result and distribution of power is most often very far from reflecting the distribution of votes cast, ie. the result is far from proportional, or fair.
  • It often gives artificially-strengthened governments, who can govern effectively, sometimes with huge landslides, without commanding a majority of votes cast.
The Single Transferable Vote system, which is sought by the Lib Dems, is a preferential voting system. These are where voters rank the candidates in order of preference, ie. I vote Lenny Labour #1, Libby Liberal #2, Cunty Conservative #3, etc. There are many different sorts of preferential systems.

STV is generally used for multiple-winner systems. It doesn't have to be, but usually it has large constituencies which have several representatives to elect. So you'd have three or four MPs covering an area the size of three or four of our current constituencies. The larger the constituencies, the more proportional the final result can be.

STV works by setting a number of votes for the winning line (or quota). This number is (generally) equal to (the number of valid votes cast divided by (the number of seats + 1)) + 1. Any candidate who gets that more #1 votes than the quota is elected.
\mbox{votes needed to win} =  \left({{\rm \mbox{valid votes cast}} \over {\rm \mbox{seats to  fill}}+1}\right) + 1
If they have more than that number of votes, those surplus votes are transferred to the candidates marked #2 on those votes. If no-one else now reaches the quota, the candidate with the least votes is eliminated, and all of their votes are now transferred to the #2 on those votes. This continues until all the seats are filled.

STV's major advantage is that it can produce the most proportional results of the three systems. It minimises 'wasted' votes - people are able to vote with their hearts and avoid 'tactical' voting. However, it is relatively complicated. It also breaks the link between one constituency area and any particular representative. Due to that broken link, it is difficult to replace MPs who resign or die between general elections, ie. it is awkward to hold by-elections.

The Alternative Vote Plus system uses a mixture of Alternative Vote (aka Instant Run-off) and a party list system.

Under AV around 80% of MPs are elected in single-member constituencies, as we do now under FPTP. However, like in STV, voters rank the candidates according to their preference. Once the #1 votes are counted, if there is no outright winner, the candidate with the least votes is eliminated. Those who voted #1 for that candidate now have their #2 votes allocated. If there is still no winner, the candidate with the next least votes is eliminated and their #2 (or #3 if their #2 vote is for the other eliminated candidate) vote is allocated. And so on until a winner is found.


This elects a rump of MPs who are tied to their constituency. The remaining members are allocated from party lists. Voters have a second vote which they use to vote for a party. Based on how many votes each party gets, the party gets allocated a proportional number of MPs from their list. There is also a variation using open party lists, where voters can choose which of the party list candidates they prefer.

The advantages of AV+ are that
  • it maintains a connection between a single MP and a particular area
  • it is more proportional than FPTP
  • it would permit strong governments and diminish sway of extremists
Disadvantages are
  • it is not truly proportional and would permit disproportionately strong governments
  • it leads to two classes of MP, directly elected and those from party lists
In German elections a system of AV+ is used which splits 50/50 between the directly elected representatives and those elected through the party lists. This enables a much greater degree of proportionality than the 80/20 split suggested for the UK.

In the UK it seems to be a very important to have a majority of directly elected MPs. Other countries do not seem as concerned about this issue. The more directly elected MPs you have, the more you impinge on proportionality, and the more 'wasted' votes you allow in your system. However, the more MPs you elect via party lists, the more power you give the party hierarchies, because they control access to the lists. To some extent, having open party lists can counteract that.

This is by far the straightest-laced post I've ever posted here. All the dozing in front of the election results must have addled my mind. My inner politics geek has awoken from a 20-year slumber and he's out for revenge. Watch your back.
images courtesy of wikipedia


Update #1
Average number of votes per seat won (courtesy of) :
  • Labour - 33,338
  • Tories - 35,021
  • Libs - 119,397

Update #2
You could read my blog. Or you could just watch John Cleese explaining PR in a SDP/Liberal Alliance Party Political Broadcast in 1987. Not as funny as he thinks he is, but he gives a pretty good overview. (Via)

No comments: