In 1993 New Zealanders voted 54-46 in favour of a new proportional representation voting system.
At the same time they voted in their last single-member simple majority system. In that election the Nationals 35 per cent of the vote and 50.5 per cent of the seats. Labour got 34.5 per cent of the vote and 45.5 per cent of the seats. The alliance got 18 per cent of the vote and 2 per cent of the seats. NZ First got 8.5 per cent of the vote and 2 per cent of the seats and others got the rest.
The system’s disadvantage was that a leftist majority of 52.5 per cent of the vote resulted in a rightist majority of seats. The advantage was a stable majority government.
The new system promises that in a 120 seat Parliament each party will get seats almost precisely in accordance with the percentage of its vote.
But it is a complicated system.
Each voter has two votes: one for a constituency seat and the other for a party list (either Maori or general). There are 60 general constituency seats and five Maori constituency seats for voters on the Maori roll. In these votes are cast and counted in much the same way as in Britain. The person with the most votes wins (no preferences).
Then the party list votes are counted and the percentage for each party calculated. That percentage is then translated to a number of seats as a percentage of the total of 120 seats. The constituency seats won by each party are then topped up to that number of seats.
For example, Labour might win 40 per cent of the party vote and, say, 20 of the sixty constituency seats. The 40 per cent entitles it to 48 of the 120 seats (that is 40 per cent of 120). So its 20 constituency seats are topped up to 48 seats by taking the top 28 candidates who have not won a constituency seat off its party list.
Voters can vote for a local member of one party for a different party in the national party list.
There are several quirks.
First, a party must get at least 5 per cent of the party vote or at least one constituency seat before its total percentage vote is translated into seats. So a party getting one constituency seat and, say, 4 per cent of the party vote would be entitled to 5 seats (4 per cent of 120), so its one constituency seat is topped up to 5. Another party that got no constituency seats and 4 per cent of the party vote would get no seats.
Secondly, if a constituency member dies or retires, a normal by-election is run. And the seat could change hands irrespective of the total proportion of the party vote. So constituency members can be a liability for a party. If a list member retires or dies the next available candidate on the list is elected.
It has been rare in New Zealand for a party to get 50 per cent of the vote, but the old system usually resulted in one or other of the two major parties getting 50 per cent of the seats with a lot less than 50 per cent of the vote. But under the new system a minority or coalition government is inevitable.