Electoral System of New Zealand - MMP in New Zealand

MMP in New Zealand

Up till 1994, New Zealand used the First past the post electoral system whereby which ever political party won the most seats on election day became the Government. This process favours two party systems and for the last 60 years, New Zealand elections have been dominated by the National Party and Labour Party. Smaller parties found it hard to gain representation and in 1994, New Zealand officially adopted mixed member proportional representation (MMP) as its electoral system. Its defining characteristic is a mix of members of Parliament (MPs) from single-seat electorates and MPs elected from a party list, with each party's share of seats determined by its share of the party vote nationwide. The first MMP election was held in 1996. As a result, National and Labour lost their complete dominance in the House. Neither party has yet been able to govern on its own and has had to form coalitions in order to govern. The closest either party has come to governing alone was the 2011 election, when National won 59 seats, just 2 short of a majority.

Under MMP, New Zealand voters have two votes. The first vote is the electorate vote. It determines the local representative for that electorate. The electorate vote works on a plurality system whereby whichever candidate gets the greatest number of votes in each electorate wins the seat. The second vote is the party vote. This determines the number of seats each party is entitled to - in other words, the proportionality of the House.

Thresholds: There are two thresholds in the New Zealand MMP system. The first is that any Party which receives 5% or more of the Party vote is entitled to a share of the nominally 120 seats in the House of Representatives - even if the Party doesn't win a single electorate seat. For instance in the 2008 elections, the Greens failed to win any electorate seats but won 6.7% of the party vote and earned nine seats in Parliament.

The second threshold is that any Party that wins one or more electorate seats is entitled to additional (list) seats in parliament even if it doesn't win 5% of the Party vote. In 2008, the ACT Party won only 3.6% of the Party vote. But this gave ACT a total of five seats altogether because one of its candidates won the Epsom electorate.

Seats in parliament are allocated to electorate MPs first. Then Parties fulfil their remaining quota (based on their share of the Party vote) from their list members. If a Party has more electorate MPs than proportional seats, then it receives an overhang. If the Party does not have enough people on its list to fulfil its quota, then there is an underhang.

At the 2011 general election, a referendum turned out in favour of retaining the MMP system. See New Zealand voting method referendum, 2011.