Why are there so many small parties?

As fast as one party goes out of Parliament, another comes in, it seems. We seem stuck around seven. How come?

Mauri Pacific, the post-1998 New Zealand First splinter, disappeared in the 1999 election but the Greens came in. The Alliance disappeared in 2002 but left behind a splinter, Jim Anderton’s Progressive party.

This election will confirm the Maori party, a splinter of Labour, to make up the numbers if ACT goes. If Anderton makes this coming term his last Destiny is out there fishing in the moral conservative catchment.

Why this diversity? After all, it took the Germans, whose system we copied, just four elections to get to three.

First, society is more diverse than in the halcyon two-party-politics days (in 1951 National and Labour shared 99.8 per cent of the vote). So you would expect a spread of parties. Germany now has five.

Second, the system was skewed by the 1986 royal commissioners’ recommendation of full proportionality for parties which win an electorate seat. This special “waiver” of the 5 per cent threshold was copied from Germany along with the rest of MMP. The commission’s chair, Sir John Wallace, volunteered in April 2002 that it was a mistake.

Self-evidently so. In 1996 the Christian Coalition got 4.3 per cent but no seats. In 1999 New Zealand First got 4.3 per cent and five seats, thanks to Winston Peters winning Tauranga by 63 votes.

If Peters had been a lone MP after 1999, would he have rebounded in the 2002 election to 10.4 per cent of the votes and 13 MPs?

Maybe. Peter Dunne survived as a lone MP from 1996 to 2002 before his windfall in that election and Peters did do a stint as a lone MP in 1992-93. But it is hard going. Few MPs, Peters included, would relish indefinite lone representation.

What might reduce the numbers?

First, the two main parties might lift their combined share of the vote and squeeze small parties into a smaller space. In 1996 and 2002 National and Labour left 38 per cent for small parties and in 1999 31 per cent. At the time of writing that space looked likely to be smaller than 25 per cent this time. If a smaller space becomes the norm, small parties without electorate seats would struggle, as ACT has this time.

Second, MMP might be changed. The most likely trigger would be a period of unstable government. Voters in this country don’t like instability, either inside parties or in their government.

National has promised a referendum but that is hollow unless Labour joins it because small parties would oppose it. Labour might, however, back a referendum if there was a period of chronic instability and it felt the public would not see it as a power grab by the two old parties — it was, after all, disgust at Labour and National that got us MMP in the 1993 referendum.

The most logical change would be to split the two votes, so that the proportional party vote is just of the 51 list MPs instead of the whole Parliament. That would more than halve the size of small parties which win few or no electorate seats.

A less ambitious change, which could probably be legislated without a referendum, would be to follow Justice Wallace’s recommendation and remove the threshold “waiver” for parties with less than 5 per cent of the party vote which win electorate seats.

But that would usually have little or no effect. In the 2002-05 Parliament only one MP, Jim Anderton’s deputy Matt Robson, would have been eliminated. And it would not of itself reduce the number of parties.

So might the voters do it anyway?

Not in a hurry. A few thousand voters in one electorate can keep a small party alive — Anderton in Wigram, Dunne in Ohariu-Belmont, Peters in Tauranga. Even an overwhelming majority of voters elsewhere can do nothing about that.

More likely leaders will do it. Take Anderton away and his party disappears. Take Peters away and New Zealand First will struggle. Take Dunne away and the dream of a true centre party fades. All three men kept electorate seats they held under the old system. Winning one from scratch now would need a new groundswell.

The parties that would endure would be those with loyal, defined constituencies, such as the Greens, possibly the Maori party and maybe a moral conservative party.

That comes to five. Which seems about right.