New Zealand held a general election on Saturday, October 14, 2023. A description of of the South Pacific nation's implementation of the Mixed Member Proportional (MMP) system, used to elect members of the House of Representatives since 1996, is presented here.

The Electoral Commission's Election Results website has detailed 2023 election results. Nationwide results are available here for the following House elections:

The election statistics presented in this space come from official reports issued by Elections New Zealand and the New Zealand Ministry of Justice.

• Historical Background
• The Electoral System
• Allocation of House of Representatives Seats in the 2002 General Election
• MMP Representation and the Party System
• Online Resources

Historical Background

A self-governing British colony from 1853 to 1907, and an independent dominion or realm within the Commonwealth of Nations since 1907, New Zealand developed a parliamentary form of government that closely followed the Westminster model. From 1913 to 1993, parliamentary elections were held on the basis of plurality or first-past-the-post (FPTP) voting in single-member constituencies called electorates.

By 1936 a stable party system had begun to take hold. Two major parties - the Labour Party and the National Party - alternated in power over the course of the following six decades. For many years, National and Labour were the only parties represented in Parliament: under FPTP, it was very difficult for minor parties with evenly spread support to win seats in Parliament.

Concerns about the fairness of the FPTP electoral system emerged as early as 1954, when the Social Credit Political League won 11.1% of the vote in the general election but no seats in Parliament. Criticism of the electoral system intensified after the 1978 and 1981 elections, in which the National Party won an absolute majority of seats in Parliament and remained in power, despite receiving fewer votes than the Labour Party. In both elections, Social Credit obtained a substantial number of votes but won very few seats in Parliament.

In 1984 the Labour Party was returned to power. The following year, the government established a non-partisan Royal Commission on the Electoral System to consider alternative systems for electing Members of Parliament. In a report released in 1986, the Commission proposed that New Zealand adopt the Mixed Member Proportional (MMP) system used in Germany. The Commission recommended MMP over other electoral systems such as the Single Transferable Vote (STV) because it retained single-member constituencies, and also because it produced more proportional seat distributions than STV. The Commission also recommended holding a binding referendum to decide the adoption of a new electoral system.

Although neither of two major parties was interested in changing the existing electoral system, both tried to use the issue to their political advantage. As a result, during the 1990 general election campaign both Labour and the National Party - which went on to win a landslide victory in the election - promised to hold a referendum on electoral reform.

In September 1992, the government held a two-part, non-binding referendum on the electoral system, in which voters were asked if they wanted to change the existing FPTP system, and then to choose among the four alternative systems considered by the Commission: MMP, STV, Supplementary Member (SM) or Preferential Voting (PV). Fifty-five percent of the electorate took part in the vote, in which a proposal to establish a new electoral system was overwhelmingly approved in the first part of the referendum, with 1,031,257 votes (84.7%) in favor, against 186,027 votes (15.3%) for retaining the existing system. In the second part of the referendum, 70.5% of the voters chose MMP as the alternative electoral system.

The overwhelming rejection of the FPTP electoral system in the 1992 referendum appeared to have been brought about by mounting voter discontent with the two major parties, both of which had broken campaign promises and pursued unpopular economic policies while in office.

In a second, binding referendum held in conjunction with a general election on November 6, 1993, voters chose between FPTP and MMP. A majority voted for MMP, which received 1,032,919 votes (53.9%) to 884,964 votes (46.1%) for FPTP, on an 85.2% voter turnout. Under the terms of a new Electoral Act previously passed by Parliament to implement MMP if that system obtained a majority of votes in the referendum, the new electoral law automatically replaced the existing electoral law.

Under the new electoral law, Parliament was expanded from 99 to 120 members. At the same time, the number of electorates was reduced from 99 to 65. The South Island was guaranteed sixteen general electorate seats, down from twenty-five under FPTP since 1965. The new electoral law retained separate electorate seats for the Maori - New Zealand's indigenous population - although their number, previously fixed at four, would be allowed to vary according to the number of Maori voters registered in the Maori electorates (voters of Maori descent may choose to register in a Maori electorate or a general electorate.)

A two-part referendum on the existing MMP electoral system was held in November 2011, along with the regularly scheduled general election. Voters were asked if they wanted to retain MMP or change to another voting system, and then choose among four alternative voting systems: FPTP, Preferential Voting, STV or Supplementary Member. Had a majority voted for change, a legally binding, second referendum would have been held in 2014, in which voters would have chosen between MMP and the alternative electoral system selected in the second part of the preceding referendum.

The Electoral System

The Parliament of New Zealand consists of a single chamber, the House of Representatives, composed of 120 members directly elected by universal adult suffrage for a three-year term of office.

The composition of the House of Representatives is determined by the Mixed Member Proportional (MMP) system, which combines elements of the single-member constituency plurality system with proportional representation (PR). Under this system, the country is divided into a number of single-member constituencies or electorates. There were 65 electorates in 1996, 67 in 1999, 69 in 2002 and 2005, 70 in 2008 and 2011, and 71 in 2014 and 2017. Electorate seats are filled by the plurality or first-past-the-post method, under which the candidate obtaining the largest number of votes in each constituency is elected.

However, in addition to nominating individual candidates at the electorate level, political parties set up lists of individuals at the national level. Each voter in New Zealand casts two votes, namely a party vote for a list, and an electorate vote for a constituency candidate. Party lists are closed, so voters may not choose individual candidates in or alter the order of such lists. The party vote is the most important of the two votes, since it is the one that determines the composition of the House of Representatives.

In the nine general elections held under the MMP system, House seats have been allocated in the following manner:

In order to participate in the proportional allocation of House seats, a party must receive at least five percent of all valid party votes cast, or win at least one electorate seat. The seats in the House of Representatives are apportioned among qualifying parties by means of the Sainte-Laguë method of PR.

The electorate seats won by a party at the constituency level are then subtracted from the total number of seats allocated to that party's list, and the remaining seats are filled by the candidates on the party list in the order determined before the election. In some instances, a party may win more electorate seats than the number of seats it is entitled to according to the result of the party vote. In such cases, the party keeps the overhang or surplus seats, and the total number of seats in the House is increased accordingly. This was the case in the 2005 general election, in which the Mâori Party won four electorate seats, but was awarded a total of three seats. The party retained its overhang seat, and the House of Representatives was expanded from 120 to 121 members.

Allocation of House of Representatives Seats in the 2002 General Election

In the 2002 general election, six parties, namely the Labour Party, the National Party, the New Zealand First Party, ACT New Zealand, the Green Party and United Future, won at least five percent of all valid party votes cast. These parties, along with Jim Anderton's Progressive Coalition, which obtained less than five percent of the vote but won one electorate seat, were entitled to participate in the proportional distribution of seats at the national level. None of the other parties that participated in the election reached the five percent threshold nor secured any electorate seats; therefore, these were excluded from the apportionment process.

To calculate the number of seats each one of the seven qualifying parties was entitled to receive, the votes polled by each of these were divided by a sequence of odd numbers starting with 1 (1, 3, 5, 7, 9 and so on - that is, the sequence 0.5, 1.5, 2.5, 3.5, 4.5 and so on, multiplied by two to obtain whole number divisors) until enough quotients had been found to allocate all 120 seats, as detailed below:

Seats were then awarded to the parties obtaining the largest quotients (shown in bold). The overall distribution of House seats can also be obtained by dividing the votes for each party by the smallest quotient used to allocate seats, multiplied by two, with remainders larger than or equal to 0.5 rounded up to the next whole number. For the 2002 election, the votes obtained by each party would be divided by the 120th largest quotient times two - 8,024.717 x 2 = 16,049.434 - with the following results:

Note that the 120th largest quotient times two is equal to the 120th largest quotient resulting from successive division of party votes by 0.5, 1.5, 2.5, 3.5, 4.5 and so on.

At this point, the electorate seats won by each party (if any) were deducted from its proportional seat allocation. For example, the 45 electorate seats won by the Labour Party were subtracted from its proportional allocation of 52 seats, so the party was awarded seven list seats. All the ACT and Green Party seats came from their respective party lists, as neither party won electorate seats.

MMP Representation and the Party System

A multi-party political system had already emerged in New Zealand in the last FPTP general election, held on November 6, 1993. Although proponents of FPTP - which was replaced by MMP in the referendum held simultaneously with the election - had promoted the system on the grounds that it led to strong, stable governments, the election-night results failed to produce a clear outcome, as no party won an absolute majority of seats in Parliament. However, the definitive results of the election gave the incumbent National Party a one-vote majority in the House of Representatives, as detailed below:

The results of the 1993 election illustrated the FPTP system's lack of proportionality. Although Labour received almost the same number of votes as the National Party, it won five percent fewer seats than the latter. Meanwhile, the Alliance - a coalition of the NewLabour, Green, Democrat (formerly Social Credit), Mana Motuhake and Liberal parties - obtained just over half as many votes as National or Labour, but won only two seats - the same number as New Zealand First, which polled less than half the number of votes obtained by the Alliance. The system clearly favored the two major parties, which obtained a combined ninety-six percent of the seats with just under seventy percent of the vote, and particularly the largest party, which secured an overall majority of seats in Parliament despite being outpolled almost two-to-one by a divided opposition.

By contrast, under the MMP system political parties are represented in Parliament in close proportion to their nationwide electoral strength. In addition, Maoris have attained representation in proportion to their population numbers. Since the introduction of MMP in 1996, no party has won an absolute majority of seats in Parliament. As a result, New Zealand governments have been either minority administrations of one of the two major parties, or coalitions with one of the smaller parties, in either case usually supported by other minor parties outside government on the basis of more-or-less formal agreements.

In the first MMP election, held in October 1996, the ruling National Party emerged as the largest party, slightly ahead of Labour. Six parties won seats in the House of Representatives. Contrary to expectations, New Zealand First joined the National Party in a coalition government, but it took almost nine weeks for the two parties to reach an agreement, which ran over sixty pages long; under FPTP, a new government was usually formed immediately after a general election.

The National-New Zealand First coalition government collapsed in August 1998. New Zealand First attempted to bring down the government, but the National Party, led since December 1997 by Prime Minister Jennifer Shipley - New Zealand's first female head of government - managed to remain in power, supported by ACT New Zealand, United New Zealand, dissident New Zealand First parliamentarians - including cabinet ministers - that remained loyal to the government, and a former Alliance M.P. who had defected from the party and subsequently formed a new political organization. This turn of events further undermined public confidence in the new electoral system, which at the time appeared to hinder government stability and effectiveness.

Labour became the largest party in the second MMP general election, held in November 1999. Nine days after the election, Labour and the Alliance produced a one-page agreement to form a minority coalition government. The Green Party, which had left the Alliance to contest elections separately, secured parliamentary representation on its own right for the first time and supported the Labour-Alliance government in Parliament. Labour Party leader Helen Clark became New Zealand's first elected female Prime Minister. Meanwhile, New Zealand First was able to secure five seats in Parliament with only 4.2% of the party vote by winning the electorate seat of Tauranga, where party leader Winston Peters was elected with a majority of sixty-three votes out of 33,781 valid votes.

The relative stability of the Labour-Alliance coalition government gradually improved public perceptions of MMP. In an opinion survey carried out in June-July 2001 by the New Zealand Election Study, a majority of respondents (53%) disagreed with the statement "MMP has been a disaster and we should get rid of it as soon as possible", although only a minority (35%) believed that "MMP has been a success and we should keep it." Nonetheless, slightly more respondents (46%) would have voted for MMP in a referendum than against it (44%). In addition, survey respondents preferred a coalition government (49%) to a single-party government (43%). In August 2001, a parliamentary MMP Review Select Committee recommended no major changes in the electoral system.

In the third MMP general election, held four months early in July 2002, Labour remained by far the largest party but fell short of an absolute majority in the House of Representatives, while the Alliance lost its parliamentary representation. At the same time, the National Party won its lowest ever share of the vote in a general election. Shortly after the election, the Labour Party, led by Prime Minister Helen Clark, formed a minority coalition government with Jim Anderton's Progressive Coalition. Labour also reached an agreement with the liberal United Future Party, which supports the government in Parliament.

While Labour and the National Party continued to dominate the electorate vote in 2002, winning between themselves all but three of the sixty-nine electorate seats, the party vote outcome of the 2002 general election, in which seven parties secured parliamentary representation, suggested the emergence of a Scandinavian-style (rather than a German-style) party system in New Zealand under MMP - a phenomenon which also appeared to be taking place in Scotland, where a MMP representation system known as the Additional Member System (AMS) was adopted in 1999 for electing members of the re-established Scottish Parliament.

However, this trend was reversed in the fourth MMP general election, held in September 2005. The National Party staged a significant comeback, winning a plurality of the electorate vote and almost doubling its share of the all-important party vote, where it trailed Labour by a narrow margin. At the same time, minor parties lost considerable ground in the election, save for the newly formed Mâori Party, which captured four of the seven Maori electorates. Nevertheless, the smaller parties continued to hold the balance of power in Parliament, and Labour - still the largest party in the House of Representatives - remained in power; in October 2005 the party formed a new minority coalition government with Jim Anderton's Progressives. The Labour-led government also secured parliamentary support from New Zealand First and United Future: the leaders of both of these parties became government ministers, although in an unprecedented arrangement they remained outside Cabinet.

Labour remained in office until November 2008, when the National Party won a sweeping general election victory (albeit four seats short of an absolute majority). Meawhile, New Zealand First was wiped out in the election, following a parliamentary censure of party leader (and then-Foreign Affairs Minister) Winston Peters for having knowingly failed to declare a NZ $100,000 (about US $70,000) donation to his party in 2005, and Peters' subsequent dismissal as government minister. Shortly after the election, National Party leader John Key formed a minority government, supported by ACT New Zealand, the Mäori Party and United Future; the leaders of the supporting parties became (or in the case of United Future, remained) government ministers outside Cabinet.

In a two-part referendum on the voting system held alongside with the November 2011 general election, New Zealand voted to retain the Mixed Member Proportional (MMP) voting system by a decisive margin: in the first part of the referendum, 1,267,955 votes (57.8%) were cast in favor of keeping the existing system, against 926,819 (42.2%) for changing it, and 62,469 informal votes (that is, ballots in which the voter had not clearly indicated the option for which they wished to vote). In the second part of the poll, where voters were asked to choose from among four alternative voting systems should New Zealand were to change to another system, the first-past-the-post system won a plurality of the valid votes cast - 704,117 out of 1,509,157, or 46.7% of the total - while the Preferential Voting (PV), Single Transferable Vote (STV) and Supplementary Voting (SV) systems trailed far behind. However, there were more informal votes (a total of 748,086) than votes cast for any of the alternative systems, and in any event the outcome of the referendum's first part rendered moot its second part.

Meanwhile, the National Party scored a landslide victory in the general election, although the party remained two seats short of an absolute majority. Nevertheless, Prime Minister Key continued in office as head of a minority government, after reaching confidence and supply agreements with United Future, ACT New Zealand and the Mäori Party. The opposition was comprised by Labour, which fared badly and polled what was at that point its worst party vote result since the introduction of MMP in 1996; the Green Party, which reached a double-digit share of the party vote for the first time ever; New Zealand First, which staged a comeback and returned to Parliament after a three-year absence; and Mana, a Mäori Party breakaway which won one Mäori electorate seat.

Online Resources

• Election Resources on the Internet: New Zealand
• New Zealand Parliament

Copyright © 2003-2023 Manuel Álvarez-Rivera. All Rights Reserved.
Last update: October 14, 2023.