Electoral Systems: A Comprehensive Overview

Introduction

• Electoral systems are a crucial aspect of political science, influencing the success of parties and candidates.

• This chapter focuses on the electoral system, which governs how votes are cast and seats are allocated.

• Other sets of rules, such as referenda, election spending, and political broadcasting, are covered elsewhere.

Diversity of Electoral Systems

• There is significant diversity and complexity in electoral systems across democracies.

• Electoral system selection is not just a technical decision but can have major political consequences.

• Different electoral formulas applied to the same vote distribution can lead to different outcomes.

• Example: The 1983 British election saw the Tories reelected with a decrease in actual votes, suggesting a different outcome under proportional representation.

Classifying Electoral Systems

• Understanding the consequences of an electoral system requires a grasp of the existing types.

• Typologies can be based on:

  • Electoral formula: How votes are counted to allocate seats.

  • District magnitude: The number of seats per district.

  • Ballot structure: How voters express their choice.

• Classical approach: Describe electoral formulas while considering district magnitude and ballot structure.

• Three basic electoral formulas:

  • Plurality: Candidate with the most votes wins.

  • Majority: Candidate needs more than half the vote to win.

  • Proportional Representation (PR): Parties represented in proportion to votes polled.

• Mixed systems: Combine PR with either plurality or majority.

• Chronological order: Plurality (Middle Ages), Majority (early 19th century), PR (mid-19th century).

• Joseph Barthélemy (1912) predicted PR's widespread adoption, but it hasn't happened.

• PR usage has remained constant since the 1920s, around 60% of democratic countries.

• Increasing popularity of mixed systems recently.

Plurality Systems

• Plurality, also known as first-past-the-post (FPTP), is the simplest system.

• A candidate needs more votes than any other challenger to be elected.

• Usually applied in single-member districts but can be used in multimember districts.

• US presidential elections: Electoral College members are elected on a winner-take-all basis within each state.

• Bloc vote: The party slate with the most votes in a state gets all of that state's Electoral College votes. Party cohesion usually allows the majority party to win most or all seats.

• Variants imagined in the 19th century to allow some minority representation within multimember districts include:

  • Cumulative vote: Voters granted as many votes as there are members to be elected, allowed to cumulate votes on a single candidate to enhance chances of minority representation.

  • Limited vote: Each voter has fewer votes than the number of members to be elected.

  • Single nontransferable vote (SNTV): Electors cast a single vote in a district electing multiple members.

• Post-Pinochet Chile has two-member districts: the leading party gets both seats only if it polls twice as much as the party that came second, otherwise, one seat goes to each of the two leading parties.

• Argentina: two seats in each province go to the leading party while the third goes to the party that came second in the popular vote.

Majority Systems

• Majority systems require a candidate to obtain more than half of the votes.

• Without further specification, there may be no winner in a single-round election or a succession of indecisive ballots.

• Variants:

  • Majority-Runoff Systems: Requires a majority on the first ballot. If no candidate obtains a majority, a second and final ballot is held between the top two candidates.

  • Majority-Plurality Systems: If no majority is reached on the first ballot, a second round is held, and the winner is the candidate with a plurality of the vote.

  • Alternative Vote: Voters rank candidates in order of preference. First preferences are counted initially, and the candidate with the smallest number of first preferences is eliminated. Second preferences from eliminated candidates are transferred until one candidate secures a majority.

Proportional Representation (PR)

• PR can be used only in multimember districts.

• Two major types of PR systems:

  • List Systems: Involve making five major decisions: districting, formula, tiers, thresholds, and preferences for candidates.

  • Single Transferable Vote: In force only in Ireland.

List Systems

• Involves five major decisions:

  • Districts: Can range from the whole country as a single electoral district to smaller, administrative subdivisions.

  • Electoral Formula: Two basic options for seat distribution within each district: highest averages methods and largest remainders methods.

  • Highest averages methods: requires the number of votes for each party to be divided successively by a series of divisors: seats are allotted to the parties that secured the highest resulting quotients, up to the total number of seats available

    • D’Hondt formula: Divisors are 1, 2, 3, 4, etc.

    • “Pure” Sainte-Laguë formula: Divisors are 1, 3, 5, 7, etc.

    • Modified Sainte-Laguë formula: The first divisor is 1.4 instead of 1.

Table\ 2.1: Distribution\ of\ Seats\ by\ the\ Three\ Highest\ Averages\ Methods

- Largest remainders (LR) systems: involves two successive operations. First, the number of votes for each party is divided by a quota, and the resulting whole number corresponds to the number of seats each party initially gets. Second, seats still unallocated are awarded to parties that had the largest surpluses of unused votes (known as remainders) following division.
  - Hare quota: Total number of votes polled in the district divided by the number of members to be elected.
  - Droop quota: Total number of votes polled in the district divided by the number of members to be elected plus one.

Table\ 2.2: Distribution\ of\ Seats\ by\ the\ Two\ Largest\ Remainders\ Methods

• Tiers: Adding a second tier of distribution, generally in order to reduce distortions resulting from the allocation of seats in the first tier

  • Pooling at the higher level of remainders from local districts.

  • Using the higher tier as a corrective.

  • Members elected at the higher level to be selected independently of members elected in basic districts.

• Thresholds: Legal thresholds of exclusion. Political parties that fail to secure a given percentage of the vote are typically excluded from parliamentary representation.

• Preferences for Candidates: Voters may or may not be allowed to express preferences for individual candidates.

  • Closed list: Voters are not allowed to express any preference for individual candidates and members are elected in the order specified on the party list.

  • Open list: Voters may express a preference for one or more candidates within the party list they voted for.

  • Panachage: Voters have as many votes as there are seats to be distributed in the district and may freely distribute those votes among candidates irrespective of the party they stand for.

Single Transferable Vote (STV)

• STV does away with party lists, thus giving voters more freedom.

• Candidates are grouped on a single ballot, to be rank ordered by voters as in the alternative vote. There is no obligation for voters to express preferences for the candidates of a single party, which makes it an instance of panachage.

Mixed Systems

• Mixed systems use different formulas (plurality and PR, majority and PR) simultaneously in a single election.

• There are at least three ways of mixing PR with either the plurality or majority rule:

  • Coexistence: Apply PR in some parts of the national territory, and either plurality or majority everywhere else.

  • Superposition: Two tiers of members, some elected by PR, the others elected by plurality or majority throughout the country.

  • Corrective: PR seats are distributed in a corrective way to compensate weaker parties that did poorly in single-member seats and to produce a parliament where each party gets its fair share of seats.

Political Consequences of Electoral Systems

• Two types of consequences:

  • Psychological effects: How parties and voters react to electoral rules.

  • Mechanical effects: Direct results of electoral rules.

The Psychological Effect

• Electoral rules affect the behavior of parties and voters.

• Does the number of parties contesting an election depend on electoral rules?

  • Elites refrain from forming new parties in plurality systems because it is more difficult for small parties to win seats.

The Mechanical Effect

• The electoral law determines how votes are to be translated into seats.

• The most direct issue regarding the mechanical impact of electoral systems thus pertains to the relationship between the proportion of votes a party gets and the proportion of seats it wins in the legislature.

Is There a Parliamentary Majority?

• The ultimate objective of an election is to determine who will govern.

• Clearly, parliamentary majorities are infrequent in PR systems.

• Parliamentary majorities, either natural or manufactured, are much more frequent in plurality elections.

The Debate Over Electoral Systems

• Which is the best electoral system?

• The dominant debate in the literature has been between plurality and PR systems.

• The basic argument in favor of the plurality rule is that it produces one-party majority government, while PR is advocated because it produces broad and fair representation.