Plurality voting system

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Image:Plurality ballot.svg
An example of a plurality.
Commonly used
Electoral systems

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The plurality voting system is a system used to elect members of a parliament which is based on single member constituencies.

The most common system, used in Canada, India, the UK, and the USA, is first past the post or winner-take-all, a voting system in which a single winner is chosen in a given constituency by having the most votes, regardless of whether or not he or she has a majority of votes.

In some countries such as France a similar system is used, but there are two rounds: the "two-round" or "two-ballot" plurality system. The two highest-voted candidates of the first round compete in a two-candidate second round.

In political science, the use of the plurality voting system alongside multiple, single-winner constituencies to elect a multi-member body is often referred to as single-member district plurality or SMDP [citation needed]. Plurality voting is also variously referred to as winner-take-all or relative/simple majority voting; however, these terms can also refer to elections for multiple winners in a particular constituency using bloc voting.

The famous works of Arend Lijphart use the term "majoritarian" systems, which is used almost synonymously with "plurality" systems.


[edit] First past the post

The term first past the post (abbreviated FPTP or FPP) was coined as an analogy to horse racing, where the winner of the race is the first to pass a particular point on the track (in this case a plurality of votes), after which all other runners automatically and completely lose (that is, the payoff is "winner-take-all"). There is, however, no "post" that the winning candidate must pass in order to win, as they are only required to receive the largest number of votes in their favour. This sometimes results in the alternative name "furthest past the post".

Historically, FPTP has been a contentious electoral system, giving rise to the concept of electoral reform and a multiplicity of different voting systems intended to address perceived weaknesses of plurality voting.

Plurality voting is used in 43 of the 191 countries in the United Nations for either local or national elections. Plurality voting is particularly prevalent in the United Kingdom and former British colonies, including the United States and Canada. <ref>"The Global Distribution of Electoral Systems"</ref> See Westminster system.

[edit] Voting

In single winner plurality voting, each voter is allowed to vote for only one candidate, and the winner of the election is whichever candidate represents a plurality of voters, that is, whoever received the largest number of votes. This makes the plurality voting system among the simplest of all voting systems.

In an election for a legislative body, each voter in a given geographically-defined electoral district votes for one candidate from a list of candidates competing to represent that district. Under the plurality system, the winner of the election acts as representative of the entire electoral district, and serves with representatives of other electoral districts.

In an election for a single seat, such as president in a presidential system, the same style of ballot is used and the candidate who receives the largest number of votes represents the entire population.

[edit] Ballot types

Generally, plurality ballots can be categorised into two forms. The simplest form is a blank ballot where the name of a candidate is written in by hand. A more structured ballot will list all the candidates and allow a mark to be made by a single candidate, however a structured ballot can also include space for a write-in candidate as well.

Plurality voting is based on minimal information — a person's vote can be entirely represented by a binary choice, so anything can be used to signify a vote — the ancient Greeks would vote on ostracising someone by scratching the name of the person to be ostracised on a piece of pottery. Votes cast as physical objects can also create a realistic display of the election results, such as an array of candidates with jars filled with differently coloured beans, with the winner being the most-filled.

[edit] Examples of plurality voting

[edit] Simple example

The election of a Member of Parliament in the UK is a well known example of the First Past the Post electoral system. But the system is also used on a smaller scale.

For this example, consider the election for the president of a school class. Each class has a president, who sits on a school council. Further assume that, in this imaginary school, male and female students disagree with each other on most issues, and students prefer to vote for others of the same sex as themselves.

In our hypothetical election, there are three candidates: Amy, Brian and Cathy. Each class member gets a ballot, with these three names on it. Each voter must put an "X" by one of the names on their ballot.

[edit] The election for class president

After the election finishes, the papers are sorted into three piles--one for votes for Amy, one for votes for Brian, and one for votes for Cathy.

The largest pile decides the winner. If Amy's pile has 11 votes, Brian's has 16, and Cathy's has 13, Brian wins.

Notice that there were a total of 40 votes cast, and the winner had only 16 of them — only 40%.

Note that the class members (the "electors") only vote once, and their votes help to choose both a class president and a member of the school council (the same person).

[edit] The election for school council

Suppose that all the other classes hold similar elections. Across all the classes, 8 of the class presidents that were elected were girls, and 9 were boys. That makes the boys the overall winner. The only influence that the pupils in this particular class had was to vote for Amy, Brian or Cathy to represent themselves.

Some might argue that a boy won for this class because there were two girls, who "split the vote": some of the girls in the class voted for Amy and others for Cathy. Perhaps if Amy had not been a candidate, all the girls would have voted for Cathy and she would have won this class; this in turn would make the girls the winners of the whole council. Arguments exactly like this, but on a larger scale, are common wherever there are plurality elections.

[edit] More complex example

Imagine that the population of Tennessee, a state in the United States, is voting on the location of its capital. The population of Tennessee is concentrated around its four major cities, which are spread throughout the state. For this example, suppose that the entire electorate lives in one of these four cities, and that they would like the capital to be established as close to their city as possible.

The candidates for the capital are:

  • Memphis, the state's largest city, with 42% of the voters, but located far from the other cities
  • Nashville, with 26% of the voters
  • Knoxville, with 17% of the voters
  • Chattanooga, with 15% of the voters

The preferences of the voters would be divided like this:

42% of voters
(close to Memphis)
26% of voters
(close to Nashville)
15% of voters
(close to Chattanooga)
17% of voters
(close to Knoxville)
  1. Memphis
  2. Nashville
  3. Chattanooga
  4. Knoxville
  1. Nashville
  2. Chattanooga
  3. Knoxville
  4. Memphis
  1. Chattanooga
  2. Knoxville
  3. Nashville
  4. Memphis
  1. Knoxville
  2. Chattanooga
  3. Nashville
  4. Memphis

Voting is accomplished whereby each voter in each city selects one city on the ballot (Memphis voters select Memphis, Nashville voters select Nashville, etc.) Votes are tabulated; Memphis is selected with the most votes (42%). Note that this system does not require that the winner have a majority, but only a plurality. Memphis wins because it has the most votes, even though 58% of the voters in this example preferred Memphis least.

[edit] Advantages

[edit] Simplicity

Plurality may well be the simplest of all voting systems. This implies specific advantages. It is likely to be quicker, and easier to administer; this may also imply that an election costs less to run. It may also have an effect on voters, because it is easy to explain and understand. Alternative voting systems may alienate some voters who find the systems hard to understand, and who therefore feel detached from the direct effect of their own vote.

In addition, not all voters see party politics or policies as a major issue. Some voters see an election primarily as a form of recruitment for an individual representative, a point of contact between the state and themselves. FPTP gives such voters a direct choice of single candidate, with no extra votes to be shared or balanced between parties. This may be especially important to voters who want to vote for individuals based on particular ethical frameworks that are not party aligned, and who do not want their vote to have a "side effect" of electing others they may not approve of.

[edit] Each representative must be a winner

Sometimes, the voters are in favour of a political party, but do not like specific candidates. An example was the premier of Alberta, Don Getty. His government was re-elected in 1989, but because of voter dissatisfaction with the way the government was led, Getty, the leader of the Alberta Progressive Conservative Party, was not re-elected by voters from his electoral district.

However this can also have the opposite effect. A candidate who is very popular among the electorate in general may lose if the candidate or the candidate's party is unpopular or has caused dissatisfaction in his or her seat. An example was how Winston Churchill lost the 1945 UK Parliamentary elections. Churchill had over a 90% approval rating, but the Labour Party won overall defeating Churchill's Conservative Party and making Clement Attlee the Prime Minister.

Similarly, in the 1999 Ontario provincial election, Mike Harris and his Progressive Conservative party was re-elected to a majority government, but symbolic of the growing discontent among voters about cuts to education, his education minister and strong ally was resoundingly defeated by the opposition candidate.

It is often claimed that because each electoral district votes for its own representative, the elected candidate is held accountable to his own voters, thereby helping to prevent incompetent, fraudulent or corrupt behavior by elected candidates. The voters in the electoral district can easily replace him since they have full power over who they want to represent them. In the absence of effective recall legislation, however, the electors must wait until the end of the representative's term. Moreover, it is possible for a winning candidate or government to increase support from one election to the next, but lose the election, or vice-versa. Also, it is generally possible for candidates to be elected if the party regards them as important even if they are fairly unpopular, by moving the candidate to a safe seat which the party is unlikely to lose or by getting a candidate in a safe seat to step down. On the flip side, in a parliamentary system, a candidate who is popular nationally may be removed if he is unpopular in his own district. This feature, however, is also present in every proportional system in existence other than a closed party list.

Although it may seem as if Single-member districts give a higher threshold and require a greater quality of the candidates to be elected, in actuality a representative in a proportional multi-member district of 5 or so people must get more votes than a representative who represents one of 5 single member districts in the same area - so it could actually be argued that it is single-member districts which lower the bar. Although each person in a single-member district must get 50% to be elected, this disenfranchises the other 50%, so in total less than 25% of the population is usually involved in the decision making process. So, while each person can be said to be a winner in a single-member district system, each decision of the legislative body cannot, while in a proportional system it can.

[edit] Preservation of One Person One Vote principle

The arguments for a plurality voting system rely heavily on the preservation of the "one person, one vote" principle (often shortened to OMOV for "one man, one vote" or more recently "one member, one vote"), as cited by the Supreme Court of the United States, wherein each voter is only able to cast one vote in a given election, where that vote can only go to one candidate. Plurality voting systems elect the candidate who is preferred first by the largest number of voters. Other voting systems, such as Instant-runoff voting or Single Transferable Vote also preserve OMOV, but rely on lower voter preference to arrive at a candidate earning either absolute majority or droop quota, respectively.

However, proponents of other systems, such as approval voting, point out that the OMOV principle was made to control the magnitude of districts; that each district must be relatively in proportion to one another in population. Approval voting does not actually represent some voters more than others, so the OMOV principle would be a weak one to discount it on. In any case, it could be argued approval voting grants one vote for each candidate to each voter - which they may choose not to cast, and cannot vote cumulate on one candidate.

[edit] Regionalism

FPTP also encourages regional parties which can be very popular in one geographical region but have little or no support in other parts of the electorate.

Some parts of a given country may have local support for a specific political party which may have no support in another region. In the United States for example, small parties, like the Socialist parties may have scattered support in certain municipalities, so a candidate from one of their regions may appear on the ballot there, whereas his name would not appear on the ballot in a region where the party has little support.

A good example of this is Canada, where, in 1993, the separatist Bloc Québécois formed the official opposition, despite getting only 13% of the vote. In the 2006 election, the Bloc Québécois received 51 seats (16.6% of the total seats) with 10.5% of the total votes. In contrast, the New Democratic Party received 29 seats (9.4% of the total seats) with 17.5% of the total votes.

[edit] Disadvantages

[edit] Tactical voting

To a much greater extent than many other electoral methods, plurality electoral systems encourage tactical voting techniques, like "compromising". Voters are pressured to vote for one of the two candidates they predict are most likely to win, even if their true preference is neither, because a vote for any other candidate will be likely to be wasted and have no impact on the final result. This is known as Duverger's Law.

In the example above, Cathy's voters would have done much better to have voted for Amy instead of Cathy; that way, Amy would have beaten Brian by eight votes. They would not have gotten their most desirable person elected, but rather their second choice; in this case plurality voting led to the paradoxical result that attempting to get their 1st most desired person elected led to their 3rd most desired person being elected instead. Likewise, in the Tennessee example, if all the voters for Chattanooga and Knoxville had instead voted for Nashville, then Nashville would have won (with 58% of the vote); this would only have been the 3rd choice for those voters, but voting for their respective 1st choices (their own cities) actually results in their 4th choice (Memphis) being elected.

The difficulty is sometimes summed up, in an extreme form, as "All votes for anyone other than the second place are votes for the winner", because by voting for other candidates, they have denied those votes to the second place candidate who could have won had they received them. It is often claimed by United States Democrats that Democrat Al Gore lost the 2000 Presidential Election to Republican George W. Bush because some voters on the left voted for Ralph Nader of the Green Party, who presumably would have preferred Gore to Bush. (It should be noted that despite such claims of potential Gore votes going to Nader, Gore still had a plurality of the popular vote. Bush won due to having more electoral votes.) Conversely, Republicans can claim that Ross Perot was a spoiler who enabled Bill Clinton to win the 1992 and 1996 presidential elections with a minority of the popular vote, because Perot had split the conservative vote,winning 8.4 percent of the vote,far better than Nader did,under 0.5 percent of the vote.

Such a mentality is reflected by elections in Puerto Rico and its three principal voter groups: the Independentistas (pro-independence), the Populares (pro-commonwealth), and the Estadistas (pro-statehood). Historically, there has been a tendency for Independentista voters to elect Popular candidates and policies. This phenomenon is responsible for some Popular victories, even though the Estadistas have the most voters on the island. It is so widely recognised that the Puertoricans sometimes call the Independentistas who vote for the Populares "melons", because the fruit is green on the outside but red on the inside (in reference to the party colours).

Because voters have to predict in advance who the top two candidates will be, this can cause significant perturbation to the system:

  • Substantial power is given to the media. Some voters will tend to believe the media's assertions as to who the leading contenders are likely to be in the election. Even voters who distrust the media will know that other voters do believe the media, and therefore those candidates who receive the most media attention will nonetheless be the most popular and thus most likely to be in one of the top two.
  • A newly appointed candidate, who is in fact supported by the majority of voters, may be considered (due to the lack of a track record) to not be likely to become one of the top two candidates; thus, they will receive a reduced number of votes, which will then give them a reputation as a low poller in future elections, compounding the problem.
  • The system may promote votes against more so than votes for. In the UK, entire campaigns have been organised with the aim of voting against the Conservative party by voting for either Labour or Liberal Democrats based on which is most popular in each constituency, regardless of the voters' opinions of the policies of these parties.
  • If enough voters use this tactic, the first-past-the-post system becomes, effectively, runoff voting - a completely different system - where the first round is held in the court of public opinion.

A feature of the FPTP system is that invariably, voters can select only one candidate in a single-member district, whilst in multi-member districts they can never select more candidates than the number of seats in the district. Some argue that FPTP would work better if electors could cast votes for as many candidates as they wish. This would allow voters to "vote against" a certain despised candidate if they choose, without being forced to guess who they should vote for to defeat that candidate, thus eliminating the need for tactical voting. Such a system would also serve to reduce the spoiler effect. This system is called approval voting.

[edit] Effect on representation

Image:Charter88 Results 2005 UK Election.jpg
Created by an organisation promoting proportional representation, this campaign postcard illustrates that Labour obtained a majority in Parliament despite winning only 35.2% of the national vote in the 2005 election.

The most commonly expressed disadvantage — perhaps because it is easiest to express and explain — of first-past-the-post is that it does not reflect the voter's thoughts. Thus, substantial bodies of opinion can be rendered irrelevant to the final outcome, and a party can obtain a majority of seats without a majority of the vote. Examples include the United Kingdom general election of 2005 where the new government won a majority of the seats with less than 36% of the national vote. The disproportionate nature of this system also means that whole regions may have MPs from only one party. The British Conservatives won large majorities of seats in the 1980s on a minority of votes while almost all the Scottish seats were Labour, Liberal or SNP; this disparity created tremendous dissatisfaction in Scotland.

A further example of disproportionality arose in the Canadian federal election of 1926 for the province of Manitoba. The province was entitled to 17 seats in that election. The result was very different from how people voted.

Political party % votes Number
of seats
% seats
     Conservative 42.2% 0 0%
     Liberal-Progressive 19.5% 7 41%
     Liberal 18.4% 4 24%
     Progressive 11.2% 4 24%
     Labour 8.7% 2 12%

The Conservatives clearly had the largest number of votes across the province, but received no seats at all.

The usual cause for these disproportionate results is that a party has a large number of votes across the entire territory, but they are spread out across the territory rather than being concentrated in particular constituencies. Parties with less overall support, but where that support is concentrated in particular constituencies, will win plurality in those constituencies over a party with widely distributed support.

This presents a problem because it encourages parties to focus narrowly on the needs and well-being of specific electoral districts where they can be sure to win seats, rather than be sensitive to the sentiments of voters everywhere. A further problem is that the party in power often has the ability to determine where the boundaries of constituencies lie: to secure election results, they may use gerrymandering — that is, redistricting to distort election results by enclosing party voters together in one electoral district. Moreover, it can be demonstrated that even the use of non-partisan districting methods - such as computers - to determine constituency boundaries tends to generate results very similar to those produced by a majority party with the power to gerrymander in its favour.<ref>Seats, Votes and the Spatial Organisation of Elections, Gudgin & Taylor (1979)</ref> Conversely, there are cases where there may be no possible way of drawing contiguous boundaries that will allow a minority representation.

It often seems fundamentally unfair that a party should have a substantially greater or lesser share of seats than their share of the vote. A further consequence of the system is that many such elections can be considered won before all votes are tallied, once there are no longer enough uncounted votes to override an established plurality count. Though not necessarily a disadvantage, this can produce a feeling of disenfranchisement among voters when running tallies are reported through the media.

This argument applies to most other single-winner voting systems.

[edit] How the seats can differ hugely from votes

In the FPTP system, the proportion of seats won may differ hugely from the proportion of votes received. A huge disparity between votes and seats is demonstrated below.

In the first table Labour has rightly won, but the size of its victory is unjustified by votes. Also, the LibDems have won a seat with half the Conservative vote when the Conservatives have no seats!

Data Cons.
Constituency A 40 50 10
Constituency B 45 55 0
Constituency C 40 10 50
Constituency D 35 40 25
Constituency E 40 60 0
Overall votes 200
Seats 0 4 1

[edit] How polarisation can stop seats changing hands

If a country becomes polarised, many constituencies will have strong majorities in certain seats, this will mean that marginal seats could be few and far between, making it hard for many seats to change hands when a party's vote drops.

Below are two tables of the six most marginal seats in a country. They both show the same seats but the second table is more polarised. Both show what would happen when there is a 5 per cent swing from Cons. to Labour. Amongst the non-polarised seats, Labour would make a larger gain than it would with polarised seats.

Non-polarised Cons.
Constituency A 59 41 Cons. hold
Constituency B 57 43 Cons. hold
Constituency C 54 46 Labour gain
Constituency D 54 46 Labour gain
Constituency E 52 48 Labour gain
Constituency F 51 49 Labour gain
Seats that would
change hands
-4 +4 n/a
Polarised Cons.
Constituency A 67 33 Cons. hold
Constituency B 64 36 Cons. hold
Constituency C 62 38 Cons. hold
Constituency D 59 41 Cons. hold
Constituency E 56 44 Cons. hold
Constituency F 52 48 Labour gain
Seats that would
change hands
-1 +1 n/a

[edit] Effect on political parties

Duverger's law is a principle of political science which predicts that constituencies that use first-past-the-post systems will become two-party systems, given enough time.

First-past-the-post tends to reduce the number of political parties to a greater extent than most other methods, thus making it more likely that a single party will hold a majority of legislative seats. (In the United Kingdom, 18 out of 22 General Elections since 1922 have produced a majority government.) Single party rule enables quicker decision-making with less need for back and forth negotiation; some argue that this is an advantage.

Multi-party coalitions, on the other hand, require consent among all coalition partners to pass legislation, which some argue gives small parties a disproportionate amount of power. In the UK, arguments for plurality often look to Italy where the frequent government changeovers are presented as undesirable. (This problem could be solved with separation of powers, in which the entire government didn't have to turn over just because it lost a vote.)

FPTP's tendency toward fewer parties and more frequent one-party rule can also produce disadvantages. One such disadvantage is that the government may not consider as wide a range of perspectives and concerns. It is entirely possible that a voter will find that all major parties agree on a particular issue. In this case, the voter will not have any meaningful way of expressing a dissenting opinion through his or her vote.

Another disadvantage is that fewer choices are offered to the voters, often pressuring voters to vote for a candidate with whom they largely disagree so as to oppose a candidate with whom they disagree even more (See tactical voting above); this feature pressures candidates to appeal to the extremes in order to avoid being undercut. This appeal-to-extremes operates by giving those voters who are more centrist no choice but to vote for them. The likely result of this is that candidates will less closely reflect the viewpoints of those who vote for them.

It may also be argued that one-party rule is more likely to lead to radical changes in government policy that are only favoured by a plurality or bare majority of the voters, whereas multi-party systems usually require greater consensus in order to make dramatic changes.

[edit] Safe seats

See also: Rotten borough

A safe seat is one in which a plurality of voters support a particular candidate or party so strongly that their votes for that candidate are guaranteed in advance of the election. This causes the difficulty that all other voters in the constituency can then make no difference to the result, since the winner of the seat is already known in advance. This results in serious feelings of disenfranchisement, and to abstention.

As an example Gerry Adams of Sinn Féin holds the 4th safest parliamentary seat in Westminster for his West Belfast constituency. [citation needed] In 2005 he held the safest of all 18 seats in Northern Ireland, with the highest percentage vote of any candidate in the province at 70.5%.<ref>The Other Opposition Parties at Westminster Mary Durkin and Oonagh Gay. 26 July 2006. Retrieved 25 November 2006. </ref>

[edit] Wasted votes

Wasted votes are votes cast for losing candidates or votes cast for winning candidates in excess of the number required for victory. For example, in the UK General Election of 2005, 52% of votes were cast for losing candidates and 18% were excess votes - a total of 70% wasted votes. This is perhaps the most fundamental criticism of FPTP, that a large majority of votes may play no part in determining the outcome. Alternative electoral systems attempt to ensure that almost all votes are effective in influencing the result and the number of wasted votes is consequently minimised.

[edit] Wipeout and clean sweep results

Since FPTP combined with single member constituencies generate a winner's bonus, if not winner takes all, the opposition can be left with few if any seats (see above).

It is argued that a weak or absent opposition due to an electoral wipeout is bad for the government. Provincial elections in several Canadian provinces provide suitable examples.

[edit] Disproportionate influence of smaller parties

Smaller parties can disproportionately change the outcome of a FPTP election by swinging what is called the 50-50% balance of two party systems, by creating a faction within one or both ends of the political spectrum which shifts the winner of the election from an absolute majority outcome to a simple majority outcome favouring the previously less favoured party. In comparison, for electoral systems using proportional representation small groups win only their proportional share of representation. In the United States, this mechanism falls within one major reasoning (USA, Voting act, 1970s) favoring two-party, First-past-the-post (FPTP) electoral systems.

[edit] Current events

The United Kingdom continues to use the first-past-the-post electoral system for general elections, and for local government elections in England and Wales. Changes to the UK system have been proposed, and alternatives were examined by the Jenkins Commission in the late 1990s but no major changes have been implemented. Canada also uses this system for national and provincial elections. In May 2005 the Canadian province of British Columbia had a referendum on abolishing single-member district plurality in favour of multi-member districts with the Single Transferable Vote system after the Citizens' Assembly on Electoral Reform made a recommendation for the reform. The referendum obtained 57% of the vote, but failed to meet the 60% requirement for passing.

Wales, Scotland, Northern Ireland, the Republic of Ireland, New Zealand and Australia are notable examples of countries within the UK, or with previous links to it, that use non-FPTP electoral systems.

Recent examples of nations which have undergone democratic reforms but have not adopted the FPTP system include South Africa, almost all of the former Eastern bloc nations, Russia, Afghanistan and Iraq.

[edit] Where plurality voting is used

Countries that use this system to elect the lower or only house of their legislature include:

See also: Table of voting systems by nation

The plurality election system is used in the Republic of China on Taiwan for executive offices such as county magistrates, mayors, and the president, but not for legislative seats which used the single non-transferable vote system. This has produced an interesting party structure in which there are two broad coalitions of parties which cooperate in executive elections but which compete internally in legislative elections. <ref>Making Votes Count, Gary Cox (1997)</ref>

India uses a proportional representation system for its upper house.

[edit] See also

[edit] References

<references />

[edit] External links

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Plurality voting system

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