Scotland and Wales-some simulations

For those that didn't notice, elections to Scotland, Northern Ireland and Wales's devolved Parliaments, as well as to various local authorities in England and the mayoralty and assembly of Greater London, took place on May 5.

In 1997, referendums took place in Scotland and Wales on whether country-wide Parliaments should be introduced to govern the two regions. In both cases, the proposal was successful. Further referendums were held in Northern Ireland (where the assembly was part of a comprehensive peace deal) and London in 1998, where devolved assemblies were introduced.

In order to gain cross-party support for these assemblies, the Blair Labour government decided against using a single-member plurality electoral system to elect members of the Scottish and Welsh assemblies. Instead, it was decided to use a mixed-member proportional representation system.

In London, there are fourteen members elected in single-member districts, and eleven members elected from closed party lists. Voters have two votes; one for their single-member district candidate, and one for a party list. In the districts, the candidate with the most votes is elected. Following this, all the list votes are tallied up, and the eleven party list seats are allocated using the D'Hondt method of party list proportional representation.

However, it is modified somewhat. The number that the party's vote is divided by is increased by the number of single-member districts the party has won. So, if a party wins five single-member districts, its vote will be divided by six at the beginning of the D'Hondt count. A party needs to win 5% of the vote to win any party-list seats.

A very similar electoral system is used for Scotland and Wales. Scotland is divided into eight districts. In each of these, eight to ten members are elected in single-member districts, and seven members are elected using party-lists. An identical system to the one used in London is used to allocate the party-list seats: however, there is no threshold. This is made up for by the substantially reduced number of seats to be elected in these districts. If we add all the seats in a district together, we get an effective threshold of about 4.4%; however, this is probably lower in practice, and may depend on the results of the single-member districts.

Wales is identical, except the districts are somewhat smaller. Each district elects between seven to nine members in single-member districts, and four members in the party-list system. This makes it very much less proportional

Scottish results

A couple of months ago, I wrote this blog post on decoy lists in Scotland. As it turns out, Nicola Sturgeon does not read my blog, and as a result no party in Scotland tried the decoy list strategy. While the Greens only ran district candidates in a small number of districts, this was more so that they could focus their efforts on winning list votes.

However, what if the parties had used decoy lists? The below chart shows what would have happened if only the SNP had used decoy lists; that is, their list candidates and district candidates were not affiliated to each other. 

Compared to the actual results, the SNP would gain thirty seats. The Conservatives would lose thirteen seats, Labour eleven, the Greens five, and the Liberal Democrats one. Rather than their current position of governing in minority, with support from one of the opposition parties needed to back legislation, the SNP would have a comfortable majority. 

But what if other parties had followed the SNP's strategy? This would make Scotland effectively mixed-member majoritarian, an electoral system where the aim is to add some proportionality onto a majoritarian system. The goal of mixed-member proportional representation is to make the entire result proportional.

The SNP would only gain twenty-four seats this time, with their list gains balanced out by the ability of the Conservative and Labour parties to make the same sort of gains. However, Labour would lose ten seats and the Conservatives would win nine; Labour's substantial weakness in the constituencies would be exaggerated. The Liberal Democrats would win the same number of seats, as most of their seats were won in constituencies. The Greens would be, proportionally, the biggest losers; they would lose all but one of their seats.

Following the election, and the SNP's failure to win a majority, Alex Salmond stated on his weekly radio show that the electoral system used in Scotland was responsible for the result. In an interview that appears fairly incoherent, Salmond claimed that the 'variations' that led to the SNP not winning a majority were the fault of the regional list system.

But is this the case? Well, we can test this. The below charts show the results of the election using a national list system; to be precise, such a system would allocate all the list seats in one district, covering the entirety of Scotland. As such a system would be very proportional, there are two simulations; one with a 5% threshold, and one without.

It's quite clear that Salmond is wrong, at least in that sense. The national list system would not have given the SNP a majority; in fact, in both simulations they would be in an even weaker position. They would have won only the 59 seats they won in the constituencies. As you can see, there are few other differences; the Liberal Democrats and Greens would both gain a couple of seats, as they were disadvantaged by having their vote spread out in the districts, while UKIP, which won only 2% of the nationwide constituency vote, would win two seats without a threshold, and none with one.

In the same article, Salmond also supports the introduction of a single-vote MMP system. Under such a system, voters would have one vote, for a constituency candidate. That vote, however, would count as a party vote for the party that constituency candidate was affiliated to.

Were such a system implemented in Scotland, it would have a number of effects. For a start, it would be bad news for the Green Party. The Greens only ran a few constituency candidates, and focused their efforts on the list. In most constituencies, the Greens have little chance of election, and Green voters would be pushed towards tactically voting for a more competitive contender. This would mean the Greens would win fewer party votes, and thus substantially fewer seats.

At the same time, tactical voting in the constituencies would go down somewhat. Despite the above, some people would still vote Green in the constituencies, but they would obviously vote for someone else if there was no Green candidate, which is the case in most places. Abolishing the list ballot would mean the Greens would be forced to run a candidate in every seat. The same would go for weak Liberal Democrats, Conservative and Labour candidates; partisans for these parties would be less likely to switch to more viable constituency candidates closer to their party affiliation if that meant that they could not vote in any way for the party of their first choice.

Wales

The results of the Welsh elections were, on the face of it, rather unusual. Labour's vote in the constituencies dropped by 7.6% and their regional vote dropped by about 5%, but they only lost one seat. So, how did this happen?

Well, there are a number of reasons for this. First of all, the big gainer in these Welsh elections was UKIP. This Eurosceptic party has gained substantial support in recent years, and while it failed to make much of a mark in Scotland, at the 2015 general election the party polled 13.6% in Wales. 

Rather than focusing their attention on the party-list seats, like the Scottish Greens, UKIP ran constituency candidates in all but two constituencies. This meant that the opposition vote became more split. Labour also had an efficient vote spread; only 16% of the vote for Labour was cast in the constituencies that they did not win (which constituted 26% of the electorate).

This on its own does not cause disproportionality. For example, in Scotland, the Scottish National Party received 80% of the district seats, off only 46.5% of the vote. Wales had a similar imbalance, with 67% of the seats for Labour for 35% of the vote. However, Wales was twice as disproportional as Scotland, using the Gallagher Index.

The key issue causing disproportionality in Wales is the very low number of party-list seats. In Wales, the percentage of list seats is very low for an MMP jurisdiction.

What if Wales had a similar amount of proportional seats to Scotland? I have simulated this by adding three seats to each region, thus making the percentage of list seats 46.67% (compared to 45.74% for Scotland).

Labour would be the main loser, falling from one seat short of a majority to just 40% of the Assembly. Plaid Cymru, the Conservatives and UKIP would be slightly better off. The Liberal Democrats would be the big gainer, winning four seats, up from just one. 

Overall, the Gallagher Index of disproportionality for Wales would decrease from 13.03 to 7.25, closer to Scotland's 5.6. In an area like Wales, where one party is dominant and the opposition is heavily split, increasing the number of party-list compensatory seats would be a sensible step to ensure an accountable regional government.

No, that is not what the House of Commons would look like under proportional representation

Following the 2015 United Kingdom election, a large number of news sites published projections of the result under what was described as proportional representation. Electoral reform is a frequently discussed topic in the United Kingdom (for more information on the issue, you can read my previous post on the topic), and it is usually discussed around election time. Personally, I think it is good to see discussion of electoral reform; the sort of electoral system used in the United Kingdom has a significant impact on the nation's governance.

Dec 15 in our advent calendar: Britain's 2015 election, if votes counted proportionally https://t.co/ykNSakWBcp pic.twitter.com/SwhLKRSrJT

— The Economist (@TheEconomist) December 15, 2015

However, there is an issue with these charts. The issue is that, as far as I can tell, they do not accurately represent any serious proposals made for proportional representation in the United Kingdom. These articles instead represent a national party list system as proportional representation. While this is strictly true, a national list system has a number of flaws, and no one in the electoral reform movement has supported it.

What is national list, and why is it not realistic in the UK?

National list is a very basic electoral system. It's simply the application of a party-list proportional representation system, except there is only one district, which includes the entire electorate. It can be open or closed list, although the large magnitude means that it can be hard to use open list. It's also fairly normal to have a threshold. It is used, in its purest form, in the Netherlands (with semi-open list, and a threshold of 0.67%), Fiji (open list, with a 5% threshold) and Israel (with closed list, and a threshold of 3.25%). Sweden and Denmark use an electoral system that uses districts with more open lists, and then the seats are allocated on a nationwide basis, thus making it effectively national list.

Such systems are rarely used in large countries like the United Kingdom, though. The issue with them is that it can lead to a weak connection between voters and electors, as there is no individual accountability. It would be organisationally difficult to use open lists to allocate all 650 seats, which would mean that parties would have large control over who was elected. 

The other issue with this system is that it would lead to fragmentation. One can simply look at recent elections in the Netherlands and Israel to see that proportionality, unrestricted, can lead to massive fragmentation. Certainly, thresholds could be introduced. But that would mean the end of regional parties and local independents. 

It would mean that Plaid Cymru or the SNP, for example, would not be able to win seats in many cases despite strong support in their areas. If a 5% threshold were used at this election (not an uncommon figure), the Conservatives would have 266 seats, Labour 219, UKIP 91, and the Liberal Democrats would have 56 (excluding Northern Ireland, although none of the Northern Irish parties would have any seats under this system). The SNP would have zero seats, which would surely have made the Scottish Nationalists unhappy, since they would be represented 100% by unionist parties (for more information on this, see my previous post about thresholds). This is less of an issue in smaller countries, where there is less regionalism. 

Even if a mixed-member system was used along with national lists, there would still be some of these problems. Most mixed-member systems use closed lists, so there would still be the issue of a lack of accountability. If the New Zealand-style system of allowing parties which win constituency seats to enter the list allocation was adopted, the threshold issue could be averted somewhat, but it would still be a flawed system.

What sort of systems have actually been proposed?

In its 2015 report, the Electoral Reform Society (a pro-proportional representation pressure group) published projections for the result under a variety of electoral systems.

Results exclude Northern Ireland

The 'List PR' system here is a districted system. While the Electoral Reform Society does not exactly show the districts, it appears that they are using European Parliament constituencies. This would lead to a very high average magnitude of 63. You could potentially use smaller constituencies, or use a mixed-member system (although they are large constituencies compared to Scottish and Welsh list tier districts), but this is a more realistic party list system. 

The Alternative Vote projection is self-explanatory, though I personally think the campaign would have changed if it had been in use, and the results would have been more different than that purely technical perspective, but that is obviously quite hard to model.

The other proposal is the single transferable vote. While I don't know what sort of district size would be used, this is a more likely proposal than national list; indeed, it appears to be the preferred proportional representation system of the Electoral Reform Society, despite its relatively rare use in the United Kingdom (outside Northern Ireland, only in Scottish local government). I'm not sure what the methodology is, or whether preferences 

Other proposals for electoral reform include AV+, the proposal of the Jenkins Commission into the electoral system convened (and then promptly ignored) by the Blair government. This system is similar to a mixed-member proportional system, except that there would be relatively few list seats in each district (each one of the 80 districts would only elect one or two list members), the district vote would be the alternative vote/preferential voting instead of single-member plurality, and an open list system would be used in the districts. The existence of this system was noted by the ERS, but they did not project it "on the basis that it is not used in any country and is no longer being advocated in any meaningful way".

While it is important that issues like electoral reform are discussed in the United Kingdom, it is equally important that what is presented as alternatives to single-member plurality are serious proposals. A national list system is not a serious proposal, and the projections from the ERS offer more relevant statistics of what will happen under proportional representation.

Scotland 2016-One weird trick to improve a party's seat count

With elections to Scotland's devolved parliament coming up next year, it looks almost certain that the left-wing nationalist Scottish National Party, which has been governing since 2007, will win a comfortable victory. Polling done in recent months suggests that, off their near sweep of Scotland's Westminster seats earlier this year, the SNP will win a comfortable victory, under the leadership of First Minister Nicola Sturgeon.

However, unlike in Westminster, their gains will be limited somewhat, because of Scotland's usage of a mixed-member proportional representation system. Even if the SNP wins all of Scotland's constituencies, or makes a near sweep, the mechanism of the mixed-member system (described below) will keep their vote shares aligned with their seat shares. There is an option, though, for the SNP to make use of a tactic that has been used before in MMP and compensatory mixed-member systems to avoid this, called decoy lists.

How does Scotland's electoral system work?

Initial plans for a Scottish parliament were put forward by the Wilson-Callaghan governments in 1978, following an inquiry triggered by a strong SNP performance in the 1974 election (the October one). Exact details of the electoral system are unclear, as I don't seem to be able to find the specific legislation. It seems that some variation of the plurality system was proposed. This would have likely led to a Labour-dominated assembly, and this may have been one of the reasons that the proposal was rejected in a 1979 referendum (while 51.62% of voters voted Yes, this only represented 32.8% of the electorate, substantially short of the 40% of the electorate requirement).

Shortly after this referendum, a general election resulted in a Conservative government, led by Margaret Thatcher, take office. The Conservatives had little interest in devolution, and as a result it stayed off the agenda until 1997. In this year, a Labour government, led by Tony Blair, took office. Labour were committed to devolution. A referendum took place in 1997, which resulted in a 74-26 vote in favour of a Scottish assembly, and a 63-37 vote in favour of said assembly having tax-varying powers.

In order to get broad support for an assembly from the SNP and Liberal Democrats, the Blair government proposed a proportional system. Much discussion was had on the issue of this system, but the eventual result was a mixed-member proportional system that was later adopted by London and Wales.

The system works in this manner. Voters have two votes; one for single-member districts and one for regional party-lists. The single-member districts are simple: the candidate with the most votes wins. In the regions (of which there are currently eight, each electing seven members), all the party-list votes are counted up. The D'Hondt system is applied in these regions; however, the first divisor in the sequence is increased by the number of single-member districts won by the party.

For example, if Labour wins 5 district seats and 50,000 votes, and the SNP wins 1 district seat and 40,000, Labour's vote is divided by 6, meaning that Labour's vote in the party list contest is 8,333. The SNP's vote in the party list contest is 20,000. Party list seats are then distributed using D'Hondt.

This system serves to reduce the disproportionality that happens with single-member plurality. For example, at the first election to the parliament, Labour won 53 constituency seats off 38.9% of the vote, but this strong result in the districts meant that they only won three seats in the lists, thus making the overall result relatively proportional (off 33% of the list vote, Labour won 43% of the seats).

What is a decoy list? 

A decoy list is a tactic used under a mixed-member proportional (or compensatory) system in order to turn it into a mixed-member majoritarian system. The basic idea is that you run your single-member district candidates as members of a different party to your district candidates. This means that you can avoid the penalties that these sort of electoral systems levy on parties that win big in the districts.

An example of this took place in Italy's 2001 election. At this time, the lower house of Italy used a mixed-member system called the scorporo. The voting process was similar to Scotland, except the compensatory mechanism was somewhat different; the list the winning candidate district was affilated to had its vote reduced by the votes cast for the second place candidate in the district plus one. If a candidate affiliated to the list of Party X wins 10,000 votes, and the runner-up gets 5,000 votes, Party X's list votes are deducted by 5,001.

A key element of this system is that parties are permitted to form coalitions, as parties need to win 4% of the nationwide vote to get party-list seats. As a result, a district candidate can display themselves as a candidate of a national coalition on the ballot paper, while being affiliated to a list within that coalition. All party lists were on the national ballot paper.

In the 2001 election, the centre-right coalition, Casa della Liberta (House of Freedoms), led by Silvio Berlusconi, affiliated many of their district candidates to a list called Abolizone Scorporo (Abolish Scorporo). This list used a dull symbol and was not publicised. Single-member district candidates affiliated to it used the Casa della Liberta symbol. Its only purpose was to soak up the vote reductions caused by the scorporo*. The centre-left list retaliated by running their own similar list, called Paese Nuovo (New Country). The two lists actually received some votes; 0.09% for Paese Nuovo and 0.07% for Abolizone Scorporo.

Given that statistics are vague and calculations are difficult, it's a bit hard to measure the exact impact of this tactic. However, the Gallagher index of disproportionality (measured out of 100, based on list votes) spiked from 6.91 in 1996 to 10.22. It's also notable that the Communist Refoundation Party got only 11 seats out of 630, for 5% of the vote. They relied entirely on list seats for their representation in parliament.

How would it work in Scotland?

Let's look at an example. The below table shows the result of a hypothetical election in a region. The SNP has won all 9 single-member district seats, off just 55,000 (33.5% of the vote). With what is clearly an unlucky vote distribution, Labour wins no seats and 27.4% of the vote. The Conservatives (they have the cross logo) win 21.3%, the Lib Dems win 12.2%, and the Greens win 5.5%.

If the SNP ran with their single-member district candidates affiliated to the list, they would win no list seats. Three seats would go to Labour and to the Conservatives, and one to the Liberal Democrats. This would mean that the severe disproportionality in the single-member districts would be compensated for as much as possible.

However, let's say the SNP did not run a party list attached to their district candidates. Instead, they ran a nominally independent list, called, say, the National Scottish Party, that all SNP voters voted for. As you can see, this would mean that the SNP's landslide in the district seats would not reduce their share of the list seats. They would win three of these, bringing their total up to 75% of the total seats in the region.

What if the SNP had tried this strategy in the last election? If we assume that all SNP voters would vote for the decoy list, the results would be as below.

As you can see, it would be a quite dramatic gain for the SNP. They would go from 69 to 96 MSPs, three-quarters of the parliament for 44% of the vote. This is not necessarily an accurate reflection, though. Some voters might not recognise the SNP's decoy, or, more importantly, the other parties could run decoy lists of their own as a defensive measure. This would effectively turn Scotland's electoral system into a pure mixed-member majoritarian system, with complete separation of both tiers. Given the small size of the regional districts, this would lead to a relatively disproportional electoral system (average magnitude would be 1.6).

How would it be done?

So, if you are Scottish First Minister Nicola Sturgeon, and you are reading this blog, you are probably thinking 'Great! But how do I put up a decoy list? What do I call it?'. Well, Ms Sturgeon, this is where you have to use your imagination.

Now, there are a wide variety of ways in which this particular nut can be cracked. However, my best idea is one that takes advantage of Nicola Sturgeon's personal popularity and recognition. First, Ms Sturgeon should resign her membership of the SNP, and form a new party, called, say, 'Nicola Sturgeon for Scotland' or 'Nicola Sturgeon Team'. As there are no formal membership requirements, and it could not be argued that the label was intended to confuse the SNP and the new party, as Sturgeon would not be an SNP member. This party could run in the party-list section, and it could be mentioned in SNP literature as an encouraged second vote.

Now, this article is not to present a strategy only for the SNP, and this strategy could also be used by the Scottish Conservatives, for example, who have strong local appeal in the South of Scotland. I'm not sure what sort of name recognition the Scottish Conservatives have, but had they registered their candidates in the South as independents, they would have won an extra three seats (assuming no SNP decoy and all Conservative voters voting for the independents).

What would be the consequences?

The SNP trying a trick like this would not go unnoticed in Westminster, which formally controls the election legislation for Scotland. If the Conservative government had significant doubts about the SNP's actions, and if the Scottish Conservatives were substantially hurt by decoys, there is the possibility of Westminster legislating to make decoy lists useless.

One way which they could do this would be by introducing one-vote MMP. Under this system, voters would vote only in the single-member districts, and these votes would be used to calculate the list totals, replacing the list votes in the previous system. If SNP candidates recieve 5000 votes in a region, the SNP list is credited with 5000 votes. As it is impossible to separate single-member district and list votes, this would blunt the SNP's tactic.

It's unclear what impact such a system would have on support for the parties. With one exception, no party has a marked difference between their list and district votes. The key exception, of course, is the Scottish Greens. They have adopted a policy of running lists only, in the hope of picking up list votes from left-leaning voters who, while recognising that the Greens cannot win a district seat and therefore not voting Green in the districts, are willing to vote Green in the lists. Under a single-vote system, the Greens would have a much harder time attracting voters.

Another option would be dumping the single-member districts entirely, and having a party-list system only. This option would likely prove controversial, as this has only been used in the European elections, and if it were introduced, it would probably have to have some form of mechanism to open up the lists, and give voters personal control over the elected members. Perhaps, too, the single transferable vote could be used. Scotland has experience with the single transferable vote, as it has been used in local elections since 2007. While this sounds like a good idea, the issue remains that Scotland has lots of land that is virtually empty (and for good reason). This would mean that some STV constituencies would be quite large.

This post is not intended to endorse the Scottish National Party. Indeed, this is a strategy that could be used by all of Scotland's parties. The SNP, however, is in an especially strong position to exploit this particular loophole. I would suggest that it would be advisable for Westminster to close it, in some way, to ensure Scotland's parliament continues with its original intention of proportional representation.

*The Abolizone Scorporo list was used again in the 2004 European election. In an attempt to reduce the vote for the Green party, the Abolizone Scorporo symbol was placed in the middle of the symbol for the 'Green-Greens', a right-wing Green party. Under Italian electoral law, this means the list is entitled to get on the ballot automatically.

UK election 2015:Why first-past-the-post?

In a previous post, I provided an outline of the parties contesting the UK election. For this post, I would like to discuss a particular aspect of the election: the electoral system. (For those that don't know about electoral systems, these posts might be helpful)

The single-member plurality system is used in the United Kingdom. This system is extremely simple; parties nominate candidates, voters vote for one candidate, and the candidate with the most votes wins. However, the system has complicated implications for voters and politicians, and a significant debate has taken place regarding it.

Where does it come from?

Plurality systems have been used in the UK since the beginning of elections. The system would have been considered the 'natural' way to hold elections; indeed, the only challenges to plurality were first considered in the 18th century, and systems of proportional representation were only developed around the start of the 20th.

However, single-member plurality systems are relatively new for the UK. During early electoral competition for the House of Commons, most electorates elected two members, using an electoral system where voters voted for two candidates, and the two candidates with the most votes won. Under this system, the party with the most votes usually won both seats

During the late 19th century, some electorates switched to the Limited Vote system. Under this system, some electorates were changed to elect three members, but voters still had two votes. The three candidates with the most votes won. This system created a problem for parties, as they had to divide their votes between their candidates in order to maximise their seats. However, they eventually manage to master this, making the Limited Vote ineffective in preventing single-party domination for electorates.

In the first decades of the 20th century, single-member constituencies were introduced, and by 1950, all electorates in the UK were single-member.

What does it do?

The single-member plurality system is fairly disproportional, and tends to favour large parties. It usually produces majority governments (with obvious exceptions). For these reasons, UK governments tend to be dominant in Parliament.

The system discourages the formation of national small parties, as these parties are unlikely to win seats. Parties like UKIP and the Greens are disadvantaged. However, small parties can win seats if their support is concentrated in a specific region. This is how the SNP, Respect, and Plaid Cymru can win seats, even with small nationwide votes.

For example, at the 1983 general election, the Conservative Party won 397 seats (out of 650) with 42.4% of the vote, the Labour Party won 209 seats with 27.6%, and the Social Democratic-Liberal alliance (the predecessor of the Liberal Democrats) won 23 seats with 25.4% of the vote. To put this another way, it took 0.11% of the vote to elect a Conservative MP, 0.13% to elect a Labour MP, and 1.1% to elect a Social Democratic-Liberal MP.

Why is it good?

Simplicity

Simple! (Andrew Reynolds)

Under single-member plurality, voting and understanding how votes transfer into seats is very easy. This is one of the key reasons that single-member plurality is advocated over systems of proportional representation or other majoritarian systems that are accused of being complicated. 

However, some have suggested that simplicity may not be important in electoral systems, on the basis that it is not necessary for voters to understand exactly how votes are transformed into seats: they just need to understand the basic ideas of the system. Nonetheless, certain experts are unwilling to accept this, and thus simplicity remains a popular idea.

Stable government

Single-member plurality tends to produce single-party government, at least in the United Kingdom. Unlike coalition governments, which can be unstable and indecisive, single-party governments are relatively unified, and majority governments are able to be decisive as they have control over Parliament. This has been used as an argument against the introduction of alternative voting systems, as it is feared that non-single-member plurality systems will endanger the stability of governments.

In some cases, this is right. Countries with overly proportional systems of proportional representation, like Israel or the Netherlands, tend to have unstable governments. However, this is not the case for all countries with proportional representation; Germany, for instance, has had reasonably stable government with proportional representation.

Also, some of the electoral systems proposed for the UK have not been proportional. For instance, the Alternative Vote/Instant Runoff system has been suggested. This system, while being somewhat more likely to produce minority governments, seems unlikely to produce more minority governments if Australian experience is anything to go by.

Accountability

Another argument for the use of single-member plurality is that it allows politicians to stay accountable to voters. Under single-member plurality, all MPs are directly accountable to a constituency, and the voters of that constituency are able to remove that MP easily. This is in comparison with some party list systems, where senior party members are unable to be easily removed. Under SMP, voters can (and do) remove senior party members. 

This also means that (in theory) local members are required to pay attention to their constituency, and even ministers need to ensure that their seats are happy with their representation. However, this does not always happen: members that take their seats for granted can still be re-elected. Other electoral systems also provide this accountability, so this feature is not unique to single-member plurality.

Why isn't it good?

Disproportionality

The single-member plurality system is extremely disproportional. Proportionality, in an electoral system, means how closely shares of seats are matched to shares of votes. This is measured using the Gallagher Index. Under single-member plurality, the candidate with the most votes wins, whether he wins by one vote or by fifty thousand. This creates an extremely weak link between votes and seats. It means that parties can win shares of seats far above or below their vote shares, and in some cases win all seats in a parliament with far less than all the votes. In other cases, a party can win a majority of seats with fewer votes than another party, if that other party has won large amounts of votes in safe seats.

Regional vote variations usually prevent extremely anomolous results in the UK (not so much in certain other countries that use or have used the same system). However, such results are neither impossible nor uncommon; plenty of local government elections have resulted in single-party councils.

Small parties with consistent levels of support nationwide (in the UK, those would be the Liberal Democrats, Greens, and UKIP) do worst out of single-member plurality. Regionally based parties (SNP, Plaid Cymru) can do well, while large parties with consistent support nationwide (Labour and/or Conservative) also do well. At some points in history, Labour or the Conservatives have fallen back on their regional strongholds when their national support became too low to win many seats.

One of the alternatives proposed to single-member plurality, the Alternative Vote, is also disproportional. Most of the alternatives proposed, however, have been an attempt to inject proportionality into the system.

Safe seats

One of the other problems with single-member plurality is that it can create safe seats for certain parties. A safe seat is a seat held on such a significant margin that one party is certain of winning it.

The problem with safe seats is that it reduces political participation. In a safe seat, opposition parties as well as the party holding the seat make less effort to campaign, thus meaning that people are less likely to vote. Those that do will vote for the better known government candidate, thus making the seat even more safe, thus ensuring that the opposition will campaign even less. This is borne out by the evidence; in the 2010 election, marginal seats had turnout 9.2% higher than safe seats.

It is true that the Alternative Vote system may not solve this problem; however, certain proportional systems have been shown to reduce the instance of safe seats.

"Tactical voting"

The idea of tactical voting is relatively unusual to Australians. Basically, tactical voting entails voting for a candidate that is not your favourite in order to stop  a candidate you strongly dislike.

For example, let's take a hypothetical Green voter in a marginal constituency with three candidates: Labour, Conservative, and Green. This voter most strongly supports the Greens, doesn't really mind Labour, but loathes the Conservatives. Now, during the campaign a poll comes out saying that the Conservatives are on 48%, Labour are on 45%, and the Greens are on 7%. Who does this voter vote for? Voting Green will be true to your ideology, but voting Labour will help you defeat the Conservatives.

This is a serious dilemma for minor party voters, and it is used in campaigning in tight seats. It is not unique to the UK: in the 2000 United States presidential election, a contest between Republican George W. Bush and Democrat Al Gore, supporters of Green candidate Ralph Nader faced the same dilemma. In the US, it is called the 'spoiler effect'.

There is a reason that Australian voters haven't heard of this. Under the Instant Runoff/Alternative Vote system, you can vote for your favourite candidate first, thus giving him/her your support, and put the candidate you hate last, ensuring that he/she will never get your support. 

What's been done about it?

Non-single-member plurality systems were rare in the UK for a long time. The Single Transferable Vote was used for Northern Ireland's devolved parliament and local government from 1973 onwards, and for Northern Ireland European elections from 1979 elections onwards. 

Under Tony Blair's government, however, proportional representation received a large boost. Mixed-member systems were used for the Scottish, Welsh, and London parliaments, while party-list proportional representation was introduced for European elections. An inquiry into a change from single-member plurality for the House of Commons was set up, but the government failed to act on the recommendations. Directly-elected mayors were introduced, elected using the supplementary vote. In 2007, the Labour-Liberal Democrat Scottish government introduced the single transferable vote for local elections.

The referendum

The first concrete step towards electoral reform took place after the 2010 election, when the Liberal Democrats set a referendum on electoral reform as a condition for entering government. The Conservatives promised that they would hold a referendum on the Alternative Vote.

This referendum was held in 2011. Labour, the Liberal Democrats, the Greens and UKIP all lined up in favour of the change, while the Conservatives and British National Party lined up against it. After the referendum was announced, support for the switch was high.

However, the Conservative campaign was very successful. The No2AV (as it was known) campaign recruited the support of some Labour MPs, and played off a general sense of uncertainty about how the system would work. It was claimed that under AV, voters for small parties would have their votes count multiple times (conveniently ignoring, of course, that under AV voters for all parties have their votes counted multiple times). Antony Green's blog has more detail on this.

As a result, the referendum was lost. 68% voted No, while only 32% voted Yes. Only nine counting districts out of 440 recorded a Yes majority.

What does the future hold?

It's hard to say. UKIP and the SNP are vague on electoral reform, but both supported AV. In the case of the SNP, they are likely to benefit from single-member plurality, so they may not want to press electoral reform too hard. The Greens  and Liberal Democrats explicitly support proportional representation. Labour supported AV, but it is unlikely that proportional representation is on the cards under a Labour majority government. The Conservatives view electoral reform of any sort as a Satanic plot. 

Were the Liberal Democrats to hold the balance of power, they would probably want another referendum on electoral reform of some sort. If UKIP and/or the Greens win a significant amount of votes but not many seats, this referendum may succeed, but it depends on the proposal.

It is true that political parties without the power to change electoral law have the will to change it, while parties with the power to change the law don't have the will. However, the 2015 election may be able to produce anger against single-member plurality that forces parties to change their attitudes.

United Kingdom election 2015

The United Kingdom will be holding a parliamentary election on the 7th of May. The incumbent government is a coalition between the centre-right Conservative Party, led by Prime Minister David Cameron, and the centre to centre-left Liberal Democrats, led by Deputy Prime Minister Nick Clegg. The opposition Labour Party, which is led by former Secretary for State for Energy Ed Miliband. A number of smaller parties, including the Greens, the United Kingdom Independence Party (UKIP), and the Scottish National Party.

Background

The United Kingdom is a constitutional monarchy, and has had universal suffrage since the 1920s. Before 1910, elections were mostly between the centre-right Conservatives (Tories) and the centrist Liberals (Whigs). These two parties alternated in government. However, in 1895, the Independent Labour Party contested 28 seats, but only won 1% of the vote. In 1900, Labour improved their vote slightly, and won two seats.

Over the subsequent years, the Labour Party improved their vote consistently. However, this was rarely at the expense of one single party. The Liberal Party split in 1918, with some members joining the Conservatives and some staying independent. This led to the Liberals declining dramatically over that period, to the benefit of both other parties. The Conservatives formed government after this, but lost their majority in 1923. Because neither of the other two parties wanted to deal with the Conservatives, the first Labour government was formed in coalition with the Liberals, under the leadership of Ramsay McDonald.

The McDonald government did not last, and an election was called later that year. The result was a dramatic loss for the Liberal Party, and a somewhat smaller loss for Labour. The Conservatives won a landslide majority.

While the Liberals made slight gains at the next few elections, the party split again coming up to the 1931 election. At this election, the Labour Party also split into factions supportive of a coalition with the Conservatives (led by Ramsay McDonald) and an independent party. The independent party won only 46 seats (out of 615), down from 287 at the last election.  The Liberals did poorly, winning only 33 seats; this was the first step in what would be a long decline for the party. The Conservatives, running in coalition with the various Labour and Liberal spinoffs (under the banner of 'National Government'), won a landslide 554 seats.

At the 1935 election, Labour made some gains under the leadership of Clement Atlee, while the Liberals continued their decline. General elections were postponed because of the Second World War, but an election was held in 1945. To some surprise, the wartime government of Conservative Winston Churchill was handily defeated, with Labour winning 393 seats (out of 640). The Conservatives won only 197, while the Liberals continued to decline.

The Atlee government was controversial, and lost some seats in 1950. In 1951, an election was held due to the slim majority of the government. The Conservatives won this relatively comfortably. This election was also notable for the poor Liberal performance; the Liberals only managed 6 seats, later reduced to 5. If a political party in a 625 member assembly can hold its meetings in one car, that party has serious problems.

In the next few elections, the Labour Party lost seats, and the Conservatives gained some. A significant change took place in 1964, when a hard-fought campaign resulted in a narrow Labour win, with a 2-seat majority. Harold Wilson, the Labour leader, became Prime Minister. The Liberals gained three seats, meaning that a large people mover would be required for party meetings.

Wilson was unsatisfied with his narrow majority, and called an election for 1966. This resulted in significant gains for Labour, at the expense of the Conservatives. Labour won a 46-seat majority. The Liberals gained three, while the Conservatives lost 52. One seat was won by a 'Republican Labour' candidate in Northern Ireland, one of the predecessors to Sinn Fein.

An election was called by Wilson for 1970. This election took place against a relatively gloomy economic background, and the Wilson government was defeated. Conservative leader Edward Heath took office with a majority of 14. This election was also notable for a halved Liberal seat tally of 6, and the first Scottish National MPs elected in a general election. Northern Ireland elected four members from local parties.

The 1974 election was somewhat remarkable. Strikes, trouble in Northern Ireland, and a stagnant economy reduced support for the government. Both parties were led by the same leaders as in 1970. Labour won 301 seats, becoming the largest party; however, 318 seats were needed for a majority. The Conservatives won 297. The Liberals won 14 seats, the SNP won 7, the Welsh nationalist Plaid Cymru party won 2, and one independent was elected. All Northern Ireland seats were won by local parties.

The resulting government was a minority Labour government, led by Wilson. This government did not last, and Wilson called another election for later that year. He won this, with 319 seats: a majority of 1.

Poor economic conditions reduced support for this Labour government, and even after Wilson resigned and was replaced by Chancellor (Treasurer) James Callaghan, the government continued to tank in the polls. Conservative leader Edward Heath was defeated by Margaret Thatcher, and Liberal leader Jeremy Thorpe was brought down due to a scandal. After the Labour Party failed to form a coalition with the Liberals, a no-confidence motion brought down the Callaghan government, and an election was called for 1979.

The Conservatives won the 1979 election comfortably, with 339 seats. Labour won 269, the Liberals won 11, the SNP won only 2, Plaid Cymru won 2, and as before, all Northern Ireland seats were won by local parties.

During the 1979 parliament, the Labour Party elected a left-wing leader, Michael Foot. This led to certain members of the party leaving and creating the new Social Democratic Party, which formed an alliance with the Liberals. This alliance did relatively well in the polls due to the lack of support for the Thatcher government. However, as the 1983 election approached, the Thatcher government gained support, and won comfortably. The Labour Party polled poorly, winning just 27.6% and 209 seats. The SDP-Liberal Alliance polled relatively well, winning 25.4%, but won only 23 seats.

The Conservatives won re-election comfortably in 1987, with Labour under the leadership of Neil Kinnock. However, in 1990, Thatcher resigned due to a number of policy controversies. By this point, the Conservatives were relatively unpopular. Thatcher was replaced by John Major, the Chancellor. Major led the Conservatives to the 1992 election, which he was expected to lose. However, Major won, but with a reduced majority in the Commons of 10.

The 1992 parliament went very badly for the Conservatives. A number of scandals, a poor economic situation, and divisions over Europe dramatically reduced Conservative support. At the same time, Labour was led by popular Tony Blair, who was successful in removing the more stridently socialist bits of the Labour policy. The 1997 election resulted in a Labour landslide, with Labour winning 418 seats out of 659. The Conservatives won just 168, and the Liberal Democrats won 46.

The Labour Party's first term in office was relatively successful, and Conservative leader William Hague failed to make much of a mark. Labour only lost 6 seats in the 2001 election.

However, the second term of Labour government was somewhat more controversial. The Iraq War, a number of scandals, and controversies regarding Labour's handling of immigration and healthcare led to the first significant increase in Conservative representation since 1983. Labour won 355 seats, the Conservatives won 198, and the Liberal Democrats won 62.

Blair resigned in 2007, and was replaced by his Chancellor, Gordon Brown. While Brown polled relatively well in his first months, a number of scandals involving ministers and a serious economic downturn dramatically reduced the support of his government. In the 2009 European elections, the Labour Party came third, behind the Conservatives and the United Kingdom Independence Party (UKIP); Labour won only 15.7%. In the Henley by-election to fill the seat of London mayor Boris Johnson, the Labour candidate won 3% and came fifth, behind not only the Conservative and Liberal Democrat candidates, but the candidates of the Greens and the far-right British National Party.

In the leadup to the 2010 election, Conservative leader David Cameron was widely expected to become Prime Minister. However, after a televised debate (the first of its kind) which didn't go as expected, the Liberal Democrats received a polling surge. While the surge was relatively short-lived, it took enough momentum away from the Conservatives to prevent them from winning a majority.

The results were 306 for the Conservatives (with 326 needed for a majority), 258 for Labour, and 57 for the Liberal Democrats. The Liberal Democrats chose to go with the Conservatives, seeing that a Labour-led government would be relatively unstable.

This has dramatically reduced Liberal Democrat support. Opinion polls have put them behind UKIP, and the 2014 European election resulted in them winning no seats. In the Rochester and Strood by-election, (which resulted in UKIP winning a seat), the Liberal Democrat candidate won 0.9%.

The electoral system

The electoral system of the United Kingdom is the 'first-past-the-post', or single-member plurality system. It is relatively simple: voters have one vote, and they cast it for a party candidate. The candidate with the most votes wins. This happens in every district nationwide.

A colour-coded map of the UK's electoral districts from the 2010 election (Wikimedia) Blue=Conservatives, Red=Labour. Orange=Liberal Democrat, Yellow=SNP, Light green=Plaid Cymru

This electoral system is fairly majoritarian, and tends to favour the two largest parties. The Liberal Democrats have had a consistent parliamentary presence, but their vote share has been consistently below their seat share. This goes for the other political parties, including the Greens. It also happens for the SNP and Plaid Cymru, but given that they are regionally based parties, they do better.

There have been proposals to replace the system with a more proportional one. The Electoral Reform Society has put forward proposals to replace FPTP with the Single Transferable Vote, a system already in use in Scottish local government and Northern Irish regional and local elections. As part of the coalition agreement between the Conservatives and Liberal Democrats, a referendum took place on introducing the Alternative Vote; while the proposal led in the polls in the lead-up to the campaign, a Conservative-led fear campaign led to the proposal's defeat by a significant margin.

The electoral system is likely to have a significant impact on how the government is formed. In 2005, the Labour Party won a majority off just 35%, and it is possible that a majority government may be formed off a lower amount.

Another factor will be that the Labour Party is able to win more seats off fewer votes due to lower turnout in less well off safe Labour districts. This means that there is the possibility that the Labour Party can win a majority off a relatively small share of the vote.

Party prospects

Conservative Twitter account

Conservatives

The Conservatives have been accused of making overly harsh cuts to public services during their term in office, and generally trailed in the polls from early 2012 by significant amounts. During this period, they were not only losing votes to Labour, but also to the United Kingdom Independence Party; traditional eurosceptic Conservatives have been angered by Cameron's relatively conciliatory stance on Europe and immigration.

The Conservative opening party political broadcast (in the UK, TV political paid advertising is banned, and parties are given free airtime)

However, in recent months, Conservative polling has picked up, mostly at the expense of Labour. This may be due to somewhat more optimistic economic forecasts, or due to Labour losing support to the SNP. Nonetheless, it has made the 2015 election more competitive, and it looks unlikely at this point that either party will win by a significant margin.

Incumbent Prime Minister Cameron, the Conservative leader, is relatively popular personally. However, he has announced that he will not serve a second term as Prime Minister, providing reasonably fertile ground for a Labour campaign based around leadership candidate speculation

Labour

The Labour Party are likely to make gains at this election. The party has moved significantly to the left under the leadership of Ed Miliband, who defeated his brother David in a leadership ballot following the resignation of Gordon Brown after the 2010 election loss. The Labour Party led in the polls for a significant amount of time, but have recently dropped back.

One of the reasons that the forecast for Labour is looking less optimistic is the lack of support for Labour in Scotland. Traditionally a Labour heartland, the pro-independence Scottish National Party has increased their support significantly since the independence referendum in 2014, which, ironically, was a setback for the Scottish pro-independence community. This may be because the Labour Party has alienated their (not insubstantial) pro-independence wing by strongly backing the No campaign in the referendum.

However, Labour's task is not insurmountable. For a start, it is possible that they could deal with the SNP to form a government (the Conservatives are making hay with this, so their polling must be suggesting that it is unpopular). As discussed before, the Labour Party is able to win more seats with fewer votes, so that will work to their advantage. 

Miliband is not an especially popular leader, however. Opinion polls have put his approval rating consistently below 30%, and it looks unlikely that he is the main reason for his party's success.

Liberal Democrats

The Liberal Democrats, a centrist liberal party, are going into the 2015 election with little chance of doing well. Five years of coalition with the Conservatives have dramatically reduced their support, and opinion polls have put them below both UKIP and the Greens. Leader Nick Clegg, who was the beneficiary of a polling boost going into the 2010 election, looks likely to lead the Liberal Democrats to an extremely poor result. Clegg's own seat of Sheffield Hallam is in peril, with opinion polls showing Labour ahead.

However, it looks unlikely that the Liberal Democrats will be wiped out. Incumbent MPs that have built up a personal profile might be able to hold their seats, and it looks likely that the Liberal Democrats will remain the largest nationwide party outside the Conservatives and Labour. Clegg is extremely unpopular, with opinion polls showing him to be the least popular UK party leader; however, he has been challenged for that title by Miliband several times.

United Kingdom Independence Party (UKIP)

UKIP are a right-wing populist anti-EU party, whose main policy is the removal of the United Kingdom from the European Union. They were formed from the Referendum Party, a party supporting a referendum on EU membership which contested the 1997 election. They are opposed to immigration, but are left of centre on economic issues.

The party has performed well in European Parliament elections, coming first (albeit with only 27% of the vote) in the 2014 elections. Despite this, they have been weak in general elections. In the last general election, under the leadership of former Conservative Lord Pearson, the party managed just 3%.

In the 2010 parliament, traditional Conservative (and Labour) voters have become disenchanted with what some see as an unaccountable and opaque European Union intent on removing Britain's powers. These voters have switched to UKIP. However, UKIP voters are spread across the UK, meaning that they will struggle to win many seats under single member plurality.

UKIP hold two seats in the Commons; both are hold by former Conservatives, who defected to UKIP, resigned, and won by-elections in their old seats. Mark Reckless, the UKIP member for Rochester and Strood, won with a 7.3% majority, while Douglas Carswell holds Clacton on a 35% majority. Both seats are in the traditionally conservative South of England. Given that these MPs are incumbents, these results are not strictly representative, but they do suggest that when looking at UKIP polls, it is important to look at regional results.

Scottish National Party

The Scottish National Party is a left-wing nationalist party founded in 1934, after the merger of two nationalist parties. The party's influence was marginal until the 1970s, when the discovery of oil in the North Sea led to an upsurge in support for Scottish independence. This led the Labour government to be forced to hold a referendum on the establishment of a Scottish government. While a majority voted for devolution, a turnout requirement meant that the referendum was lost. The devolution issue went on the back burner for a decade, but in 1997, the Labour Party was elected, and a referendum to implement a Scottish government was won.

The SNP came second in the first Scottish Parliament elections in 1999: well ahead of the Conservatives and Liberal Democrats, with around 28% of the vote. However, they did not repeat this success in the general election in 2001, with only 20% and 5 seats out of 72.

In the 2007 Scottish Parliament election, the SNP won the most seats: 47 seats to 46 for Labour. The party formed a minority administration with the support of the Greens. Despite this success, the SNP's performance in 2010 was lukewarm; only 6 seats.

The SNP's support in the Scottish Parliament hit a high in 2011, with the SNP winning 69 seats. This was the first overall majority for any Scottish party in the Scottish Parliament. Even that did not give the SNP's national polling a significant boost. 

However, the independence referendum seems to have polarised Scottish politics. Labour's strong campaign against independence has meant that pro-independence Labour voters seem to have switched to the SNP. The party has relatively consistent support across Scotland, meaning that it will be likely that the SNP will be the largest party in Scotland, and it is possible that they will enter a coalition with Labour.

The others

The Greens have been a relatively marginal influence in UK politics for a long time, but they won a record 15% in the 1989 European elections. The usage of single-member plurality for these elections meant that they won no seats, and they failed to repeat this success in the 1992 general election. However, they have improved their support recently, and Caroline Lucas, the former party leader, was elected to be the member for Brighton Pavillion. Their leader, the Australian Natalie Bennett, is reasonably popular, but it looks unlikely that the Greens will win many more seats.

The far-right British National Party received a boost in the 2009 European election, winning 2 seats. However, they did not repeat any of this in the 2010 General elections, winning just 1.9%. They lost their seats in the European elections, and look almost certain to do very poorly in the general elections.

George Galloway's Respect Party is a rather odd outfit. Galloway is a former Labour MP from Scotland, who was expelled from Labour in 2003 after making controversial statements about the Iraq War. He formed a new party, called Respect, and won the immigrant-dominated seat of Bethnal Green and Bow from Labour. He contested the seat of Poplar and Limehouse in 2010, but lost. He managed to win the seat of Bradford West in a 2012 by-election with a large swing. No polling has been done in this seat, so it is uncertain if Galloway will be elected, especially considering his controversial comments on Israel and Julian Assange.

Plaid Cymru is a centre-left Welsh nationalist party that supports independence for Wales. They are a significant presence in the Welsh parliament, but are weaker then the Scottish nationalists. They hold three seats in the Westminster parliament, and their polling shows that they have little chance of winning many more.

Overall picture.

It is still far too early to make any solid predictions about the UK election. However, if the polls are correct, a significant amount of votes will be cast for parties that will win few seats. This does not bode well for the future of the UK two-party system, and suggests that a switch to proportional representation may be possible.

However, it is too early to say whether this will happen. A change that large would require a referendum, and judging by the campaign waged against AV in 2011, that would be a hard referendum to win.

Nonetheless, this election is one of the closest, and one of the most interesting elections in UK history. I will be posting further on this election in the future, so please follow this blog for updates.