Over the weekend John Armstrong had a column about youth voter turnout in the upcoming election. Much of the material was familiar – young people don’t vote so much – nobody talks their language, yo! – parties are Trying Very Hard, but they are also old fuddy-duddies – and so on. But among that came this idea:
John Key’s overt pragmatism has exacerbated this trend. National’s lack of a strong ally on the centre-right has forced him to moderate National’s policy thrust. Labour’s desire not to be hostage to the Greens was reflected in Helen Clark similarly avoiding doing too much which risked angering centre-ground voters who kept her in power for nine years.
In short, MMP may bear some responsibility in depressing turnout. It cannot be blamed alone, however, for the abysmal turnout of younger voters.
I disagree, as Armstrong’s claim here runs directly-if-casually contrary to at least two large research programmes in political science.
First, proportional electoral system like MMP usually lead parties to be more widespread along the ideological scale, not bunch closer together (see Cox 1990). The incentives to bunch closer together are actually much stronger in an FPP-style system, because the large parties do not need to worry nearly as much about new parties encroaching from the extremes (see Downs 1957). So even if Armstrong is right that National and Labour are edging ever closer together:
Second, there is a lot of evidence that proportional systems like MMP actually cause voter turnout to go up, not down (see Franklin 1996, Blais 2000). That is because in FPP-style systems, almost all votes are functionally wasted because they are cast in safe districts, whereas in MMP-like systems all votes are equally valuable, wherever they are cast.
Turnout in New Zealand has been dropping steadily for a long time, just as it has in other countries. This is a secular trend. Just because turnout has dropped since New Zealand adopted MMP, it does not follow that New Zealand turnout dropped because of MMP. At the risk of descending into Sorkinisms, post hoc ain’t no propter hoc.