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First-past-the-post voting

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A ballot paper for a first-past-the-post voting system, with the voter required to mark only one candidate
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A first-past-the-post (abbreviated FPTP, 1stP, 1PTP or FPP) or winner-takes-all voting system is one in which voters are required to indicate on the ballot paper the candidate of their choice, and the candidate who receives more votes than any other candidate wins. The first-past-the-post voting method is one of the several plurality voting systems. It is a common, but not universal, feature of voting systems with single member electoral divisions. The system is widely used in India, the Philippines, the United States, the United Kingdom and Canada, and is used in many other countries.

Overview

Countries which use a first-past-the-post voting system

There is some confusion between highest vote, majority vote and plurality voting systems. All three use a first-past-the-post voting method, but there are subtle differences in the method of execution.[1] First-past-the-post voting is also used in two-round systems and some exhaustive ballots.

First-past-the-post voting methods can be used for single and multiple member electoral divisions. In a single member election the candidate with the highest number, not necessarily a majority, of votes is elected. The two-round ("runoff") voting system uses a first-past-the-post voting method in each of the two rounds. The first round determines which two candidates will progress to the second, final round ballot.

In a multiple member first-past-the-post ballot, the first number of candidates, in order of highest vote, corresponding to the number of positions to be filled are elected. If there are six vacancies then the first six candidates with the highest vote are elected. A multiple selection ballot where more than one candidate can be voted for is also a form of first-past-the-post voting in which voters are allowed to cast a vote for as many candidates as there are vacant positions; the candidate(s) with the highest number of votes is elected.

The Electoral Reform Society is a political pressure group based in the United Kingdom which advocates abolishing the first-past-the-post system (FPTP) for all national and local elections. It argues FPTP is "bad for voters, bad for government and bad for democracy". It is the oldest organisation concerned with electoral systems in the world.[2]

As of 2014, all U.S. States other than Maine and Nebraska use a winner-take-all form of simple plurality, first-past-the-post voting, to appoint the electors of the Electoral College. Under the typical system, the presidential candidate gaining the greatest number of votes wins all of the state's available electors, regardless of the number or share of votes won, or the difference separating the leading candidate and the first runner-up.[3]

Example

Template:Singaporean presidential election, 2011

Under a first-past-the-post voting system the highest polling candidate (or a group of candidates for some cases) is elected. In this real-life example, Tony Tan obtained a greater number than the other candidates, and so was declared the winner.

Effects

The effect of a system based on single seat constituencies is that the larger parties gain a disproportionately large share of seats, while smaller parties are left with a disproportionately small share of seats. It is more likely that a single party will hold a majority of legislative seats. In the United Kingdom, 18 out of 23 general elections since 1922 have produced a single party majority government. For example, the 2005 UK General election results in Great Britain are as follows:

e • d Summary of the 5 May 2005 House of Commons of the United Kingdom election results (parties with more than one seat; not incl. N. Ireland)
Seats
This table indicates those parties with over one seat, Great Britain only 		Seats % Votes % Votes
Labour Party 355 56.5 36.1 9,552,436
Conservative Party 198 31.5 33.2 8,782,192
Liberal Democrats 62 9.9 22.6 5,985,454
Scottish National Party 6 1.0 1.6 412,267
Plaid Cymru 3 0.5 0.7 174,838
Others 4 0.6 5.7 1,523,716
628 26,430,908

It can be seen that Labour took a majority of seats, 57%, with only 36% of the vote. The largest two parties took 69% of votes and 88% of seats. Meanwhile, the smaller Liberal Democrat party took more than a fifth of votes but only about a tenth of the seats in parliament.

Another example would be the UK General Election held on 7 May 2015:

Party Leader Votes Seats Votes per Seat
Conservative Party David Cameron 11,334,920 (36.8%)
331 (50.9%)
331 / 650
 34,244
Labour Party Ed Miliband 9,344,328 (30.4%)
232 (35.7%)
232 / 650
 40,277
UK Independence Party Nigel Farage 3,881,129 (12.6%)
1 (0.2%)
1 / 650
 3,881,129
Liberal Democrats Nick Clegg 2,415,888 (7.9%)
8 (1.2%)
8 / 650
 301,986
Scottish National Party Nicola Sturgeon 1,454,436 (4.7%)
56 (8.6%)
56 / 650
 25,972
Green Party Natalie Bennett 1,154,562 (3.8%)
1 (0.2%)
1 / 650
 1,154,562
Democratic Unionist Party Peter Robinson 184,260 (0.6%)
8 (1.2%)
8 / 650
 23,033
Plaid Cymru Leanne Wood 181,694(0.6%)
3 (0.5%)
3 / 650
 60,565
Sinn Féin Gerry Adams 176,232 (0.6%)
4 (0.6%)
4 / 650
 44,058
Ulster Unionist Party Mike Nesbitt 114,935 (0.4%)
2 (0.3%)
2 / 650
 57,468
Social Democratic & Labour Party Alasdair McDonnell 99,809 (0.3%)
3 (0.5%)
3 / 650
 33,270
Others N/A 349,487 (1.1%)
1 (0.2%)
1 / 650
 349,487

Here, the Conservatives took 51% of the seats with only 37% of the vote. More significantly, the Liberal Democrats and the SNP together had fewer votes than UKIP but both gained more seats; with fewer votes, they together managed to win 64 times the number of UKIP seats in parliament. It should be noted that the Liberal Democrats also suffered under first-past-the-post, by winning only 1% of the seats on 8% of the national popular vote.

Benefits

The benefits of FPTP are that its concept is very easy to understand, and ballots can be easily counted and processed. Alternative systems such as rank-based voting require far more work or processing power to tabulate results than a single choice.

Criticisms

Tactical voting

To a greater extent than many other electoral methods, the first-past-the-post system encourages tactical voting. Voters have an incentive to vote for one of the two candidates they predict are most likely to win, even if they would prefer neither candidate to win. A vote for any other candidate is considered to be likely "wasted" and bear no impact or benefit on the final result they would prefer—and in many cases, harm it.

The position is sometimes summarized, in an extreme form, as "all votes for anyone other than the second place are votes for the winner". This is because by voting for other candidates, they have denied those potential votes to the second place candidate who could have won had they received them. Following the extremely close 2000 U.S. presidential election, some supporters of Democratic candidate Al Gore believe that one reason he lost the election to Republican George W. Bush is because a portion of the electorate (2.7%) voted for Ralph Nader of the Green Party, and exit polls indicated that more of these voters would have preferred Gore (45%) to Bush (27%), with the rest not voting in Nader's absence.[4] The argument for this case is even more pronounced because the election was ultimately decided on the basis of the election results in Florida where Bush prevailed over Gore by a margin of only 537 votes (0.009%), which was far exceeded by the number of votes, 97488 (0.293%), that Nader received.

In Puerto Rico, there are 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 Puerto Ricans 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 colors).

Because voters have to predict in advance who the top two candidates will be, results can be significantly distorted:

  • In general, some voters will vote based on the sense that they not only need to think about how they will vote, but how all other voters will vote as well, which will influence and possibly change their originally intended vote (tactical voting).
  • 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 that those candidates who receive the most media attention will probably be the most popular and thus most likely to be the top two.
  • A new candidate with no track record, who might otherwise be supported by the majority of voters, may be considered unlikely to be one of the top two candidates; thus they will receive fewer votes, which will then give them a reputation as a low poller in future elections, perpetuating the position.
  • The system may promote votes against as opposed to votes for. In the UK, entire campaigns have been organised with the aim of voting against the Conservative party by voting either Labour or Liberal Democrat. For example, in a constituency held by the Conservatives, with the Liberal Democrats as the second-place party and the Labour Party in third, Labour supporters might be urged to vote for the Liberal Democrat candidate (who has a smaller shortfall of votes to make up and more support in the constituency) rather than their own candidate, on the basis that Labour supporters would prefer an MP from a competing left/liberal party to a Conservative one. However this is a subjective interpretation of the election, as it cannot be objectively measured.
  • If enough voters use this tactic, the first-past-the-post system effectively becomes runoff voting – a completely different system – in which the first round is held in the court of public opinion. A good example of this is believed to be the Winchester by-election, 1997.

Proponents of other single-winner voting systems argue that their proposals would reduce the need for tactical voting and reduce the spoiler effect. Examples include the commonly used two-round system of runoffs and instant runoff voting, along with less tested systems such as approval voting and Condorcet methods.

Effect on political parties

A graph showing the difference between the popular vote (inner circle) and the number of seats won by major political parties (outer circle) at the United Kingdom general election, 2015

Duverger's law is an idea in political science which says that constituencies that use first-past-the-post systems will become two-party systems, given enough time. Economist Jeffrey Sachs explains:

The main reason for America's majoritarian character is the electoral system for Congress. Members of Congress are elected in single-member districts according to the "first-past-the-post" (FPTP) principle, meaning that the candidate with the plurality of votes is the winner of the congressional seat. The losing party or parties win no representation at all. The first-past-the-post election tends to produce a small number of major parties, perhaps just two, a principle known in political science as Duverger's Law. Smaller parties are trampled in first-past-the-post elections.

— from Sachs's The Price of Civilization, 2011[5]

Duverger's Law is rarely seen in reality, with most first-past-the-post elections resulting in multiparty legislatures, the United States being the major exception.[6]

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. This "winner-takes-all" system may be one of the reasons why "voter participation tends to be lower in countries with FPTP than elsewhere."[7]

Gerrymandering

Main article: Gerrymandering
Diagrams with dots.
Dots represent voters; lines represent electoral districts. The diagram to the left represents a fair (ungerrymandered) election. The other diagram shows how gerrymandering can tilt the odds to favor one side.

Because FPTP permits many wasted votes, an election under FPTP is easily gerrymandered. Through gerrymandering, constituencies are deliberately designed to unfairly increase the number of seats won by one party at the expense of another.

One example includes a hypothetical pair of parties called "Red-dot" and "Blue-dot". In this example, the governing Blue-dot party wishes to reduce the seats that will be won by opposition Red-dot party in the next election. It creates a number of constituencies in each of which the Red-dot party has an overwhelming majority of votes (such as the district in the lower left hand corner.) The Red-dot party will win these seats, but a large number of its voters will waste their votes. Then the rest of the constituencies are designed with small majorities for the Blue-dot party. Few Blue-dot votes are wasted, and the Blue-dot party will win a large number of seats by small margins. As a result of the gerrymander, the Red-dot party's seats have cost it more votes than the Blue-dot party's seats. In the diagram, after the gerrymander, the Blue-dot party will win three seats and the Red-dot party only one seat, despite the existence of an equal number of voters overall for both parties.

Manipulation charges

The presence of spoilers often gives rise to suspicions that manipulation of the slate has taken place. The spoiler may have received incentives to run. A spoiler may also drop out at the last moment, inducing charges that such an act was intended from the beginning.

Smaller parties may reduce the success of the largest similar party

Under the first-past-the-post voting system, small parties may draw votes away from larger parties that they are most similar to and therefore give an advantage to another large party that they are least similar to.

In comparison, for electoral systems using proportional representation small groups win only their proportional share of representation. However, in PR systems, small parties can become decisive in Parliament, thus gaining a power of blackmail against the Government—a problem which is generally reduced by the FPTP system.[8][9]

Voting system criteria

Scholars rate voting systems using mathematically derived voting system criteria, which describe desirable features of a system. No ranked preference method can meet all of the criteria, because some of them are mutually exclusive, as shown by results such as Arrow's impossibility theorem and the Gibbard–Satterthwaite theorem.[10]

Majority criterion

checkY The majority criterion states that "if one candidate is preferred by a majority (more than 50%) of voters, then that candidate must win".[11] First-past-the-post meets this criterion (though not the converse: a candidate does not need 50% of the votes in order to win). Although the criterion is met for each constituency vote, it is not met when adding up the total votes for a winning party in a parliament.

Condorcet winner criterion

☒N[12] The Condorcet winner criterion states that "if a candidate would win a head-to-head competition against every other candidate, then that candidate must win the overall election". First-past-the-post does not[12] meet this criterion.

Condorcet loser criterion

☒N[12] The Condorcet loser criterion states that "if a candidate would lose a head-to-head competition against every other candidate, then that candidate must not win the overall election". First-past-the-post does not[12] meet this criterion.

Independence of irrelevant alternatives criterion

☒N The independence of irrelevant alternatives criterion states that "the election outcome remains the same even if a candidate who cannot win decides to run." First-past-the-post does not meet this criterion.

Independence of clones criterion

☒N The independence of clones criterion states that "the election outcome remains the same even if an identical candidate who is equally-preferred decides to run." First-past-the-post does not meet this criterion.

List of current FPTP countries

The following is a list of the countries currently following the first-past-the-post voting system.[13][14]

See also

References

  1. ^ "FairVote.org - Glossary". FairVote.
  2. ^ "Electoral Reform Society History & Goverance". Retrieved 23 October 2015.
  3. ^ "U. S. Electoral College: Frequently Asked Questions". Retrieved 23 October 2015.
  4. ^ Rosenbaum, David E. (24 February 2004). "THE 2004 CAMPAIGN: THE INDEPENDENT; Relax, Nader Advises Alarmed Democrats, but the 2000 Math Counsels Otherwise". New York Times. Retrieved 8 May 2010.
  5. ^ Sachs, Jeffrey (2011). The Price of Civilization. New York: Random House. p. 107. ISBN 978-1-4000-6841-8.
  6. ^ Duverger’s Law is a dead parrot. Outside the USA, first-past-the-post voting has no tendency at all to produce two party politics
  7. ^ Drogus, Carol Ann (2008). Introducing comparative politics: concepts and cases in context. CQ Press. p. 257. ISBN 978-0-87289-343-6.
  8. ^ Ilan, Shahar. "about blackmail power of Israeli small parties under PR". Haaretz.com. Retrieved 8 May 2010.
  9. ^ "Dr.Mihaela Macavei, University of Alba Iulia" (PDF). Retrieved 8 May 2010.
  10. ^ David Austen-Smith and Jeffrey Banks, "Monotonicity in Electoral Systems", American Political Science Review, Vol 85, No 2 (Jun. 1991)
  11. ^ Single-winner Voting Method Comparison Chart "Majority Favorite Criterion: If a majority (more than 50%) of voters consider candidate A to be the best choice, then A should win."
  12. ^ a b c d Felsenthal, Dan S. (2010) Review of paradoxes afflicting various voting procedures where one out of m candidates (m ≥ 2) must be elected. In: Assessing Alternative Voting Procedures, London School of Economics and Political Science, London, UK.
  13. ^ "Countries using FPTP electoral system for national legislature". idea.int.
  14. ^ "Electoral Systems". ACE Electoral Knowledge Network. Retrieved 3 November 2015.

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