Plurality voting system

 
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The plurality voting system is a single-winner voting system often used to elect executive officers or to elect members of a legislative assembly which is based on single-member constituencies. This voting method is also used in multi-member constituencies in what is referred to as an exhaustive counting system where one member is elected at a time and the process repeated until the number of vacancies is filled.

The most common system, used in Canada, India, the United Kingdom, and some United States elections, is simple plurality, first-past-the-post or winner-takes-all. In this voting system the single winner is the person with the most votes; there is no requirement that the winner gain an absolute majority of votes.[1]

In some countries such as France (as well as in some jurisdictions of the United States, such as Louisiana and Georgia) a similar system is used, but there are two rounds: the "two-ballot" or "runoff election" plurality system. If any candidate in the first round gains a majority of votes, then there is no second round; otherwise, the two highest-voted candidates of the first round compete in a two-candidate second round or all candidates above a certain threshold in the first round compete in a two-, three- or four-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.[2] Plurality voting is also variously referred to as winner-takes-all or relative/simple majority voting; however, these terms can also refer to elections for multiple winners in a particular constituency using bloc voting.

Contents

Terminology

Confusion in terminology is often used between Highest vote, Majority vote and Plurality voting.

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-takes-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".

In a multiple member first-past-the-post ballots the first candidates in order of highest vote to cross the line are elected. In some cases the system involves an iteration of the counting of Plurality votes.

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.

Voting

Plurality voting is used for local and/or national elections in 43 of the 191 countries of the United Nations, as well as in the Republic of China (Taiwan). Plurality voting is particularly prevalent in the United Kingdom and former British colonies, including the United States, Canada and India.[3] See Westminster system.

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 for voters and vote counting officials (it is however very contentious to draw district boundary lines in this system).

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. (The President of the United States is indirectly elected by such a rule; but see Electoral College.)

The two-round voting system uses first-past-the-post voting method in the first round of voting. In this case the two highest polling candidates that cross the line progress to the second round Run-off ballot.

In a multiple member Plurality election the counting of the ballot uses an exhaustive iteration process using the same ballot papers to elect one person each iteration for each vacant position.

Ballot types

An example of a plurality ballot.

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.

Examples of plurality voting

General elections in the United Kingdom

The United Kingdom, like the United States and Canada, uses single-member districts as the base for national elections: Each electoral district or constituency chooses one member of parliament, namely the candidate that gets the most votes, whether he reaches a majority of votes or not ("first past the post"). In 1992, for example, a Liberal Democrat in Scotland won with just 26 percent of the vote. This system of single-member districts with plurality victors tends to produce two large political parties. (In countries with proportional representation there is not such a great incentive on forming two large parties, and that contributes to multi-party systems.)

Scotland, Wales and Northern Ireland use the first past the post system for general elections in the UK, but use versions of proportional representation for local elections and European elections.

The countries that inherited the British majoritarian system tend toward two large parties, one left, the other right, such as the U.S. Democrats and Republicans. Canada is an exception to this pattern, because its third parties are territorially concentrated, especially the separatist Bloc Québécois. New Zealand used the British system, and it too yielded two large parties. It also left many New Zealanders discontent, because other viewpoints got ignored, so its parliament in 1993 adopted a new electoral law, modeled on Germany's system of proportional representation (PR) with a partial selection by constituencies. New Zealand soon developed a more complex party system.[4]

A hypothetical example

Tennessee's four cities are spread throughout the state

Imagine that Tennessee is having an election 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 these four cities, and that everyone wants to live as near to the capital as possible.

The candidates for the capital are:

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. Notice that this problem does not hold anymore in the two-round system.

Advantages

Plurality is often conflated with Single-winner voting systems in general, in order to contrast it with Proportional representation. See the advantages there for other advantages of plurality in this context, such as constituency link, regionalism, and accountability.

Preservation of "one person, one vote" principle

The arguments for a plurality voting system rely 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, although this need not be an absolute majority. Other voting systems, such as instant-runoff voting, party-list proportional representation or single transferable vote also preserve OMOV, but rely on lower voter preference to enable a candidate to earn either an absolute majority (single member district) or a quota (multi-member district), respectively.

Moderation

Some other voting systems can end giving a higher chance of victory to a candidate perceived as having extreme views. Under a first-past-the-post system, voters are often afraid of "wasting" their vote on a candidate unlikely to win, so they cast their vote towards their most preferable choice possible of victory. Advocates of plurality voting suggest that this results in most candidates having to field a fairly moderate or centrist position. This is debated by advocates of other systems, who argue that preferential voting or range voting systems, by getting more information from voters, allow a more rigorous definition of the word "moderate" and can be designed to explicitly favor candidates fitting that description.

Fewer minority parties

Plurality voting tends to promote two-party systems (even more so than other single-winner systems). Supporters view this as beneficial, as parliamentary governments, or other coalitions, are typically more stable in two-party systems, and thus small minorities are not given undue voice. First-past-the-post minimizes the influence of third parties and thus arguably keeps out extremists. However, this can also deny fair representation to positive third parties, racial minorities, women, and others.

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. On 9 February 2010 the UK Parliament voted in favour of a referendum on the possible use of the Alternative vote system.

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. An October 2007 referendum in the Canadian province of Ontario on adopting a Mixed Member Proportional system, also requiring 60% approval, failed with only 36.9% voting in favour.

Northern Ireland, Scotland, Wales, the Republic of Ireland, Australia and New Zealand are notable examples of countries within the UK, or with previous links to it, that use non-FPTP electoral systems (Northern Ireland, Scotland and Wales use First Past the Post in general elections, however).

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.

Where plurality voting is used

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

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.[5]

See also

Notes

  1. ↑ The distinction between American and British English is described by Fowler (1965) as follows: "With three-cornered contests as common as they now are, we may have occasion to find a convenient single word for what we used to call an absolute majority... In America the word majority itself has that meaning while a poll greater than that of any other candidate, but less than half the votes cast is called a plurality. It might be useful to borrow this distinction..." (Fowler, H.W. 1965 A Dictionary of Modern English Usage)
  2. ↑ ""Plurality-Majority Systems"". Mtholyoke.edu. http://www.mtholyoke.edu/acad/polit/damy/BeginnningReading/plurality.htm. Retrieved 2010-05-08. 
  3. ↑ "The Global Distribution of Electoral Systems". Aceproject.org. 2008-05-20. http://aceproject.org/epic-en/es#ES05. Retrieved 2010-05-08. 
  4. ↑ Michael Roskins. Countries and Concepts 2007.
  5. ↑ Making Votes Count, Gary Cox (1997)

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