There has been a bit of hysteria the last few days about dire consequences if New Zealand First should be returned to parliament. See PM John Key on Stuff, or the Vote For Change campaign’s highly ignorable press releases, for example.

So what’s going on? A couple of recent polls have the NZF party closing in on the 5% threshold, and the probability of NZF being returned to Parliament has shot up to about 50% on iPredict, from about 15% just over a week ago.

On top of this, NZF leader Winston Peters has made a point of saying he won’t go in to coalition with anybody, or support anybody with supply and confidence, leading observers to assume that if NZF wins seats in parliament this election everything will turn to custard and we will be having another election in the next few months.

So what would actually happen if NZF were returned to parliament?

**The current situation.**

To figure this out we run a series of simulations, firstly based on the current polling avereges. We call this “Situation #0”. It looks something like this:

Keep in mind that a party would need 63 seats to win a majority:

So National is therefore almost guaranteed an outright majority in the house:

So there you have it.

**What if NZF makes 5%?**

And what would happen if NZF just makes the 5% threshold? Firstly lets simulate this by assuming that NZF takes the same number of votes from National and Labour such that they get exactly 5%. We call this “Situation #1”. Under Situation #1 NZF would win exactly 6 seats. And the other parties?

So with NZF taking 1% or so of the vote from each of National and Labour and winning 6 seats, National and Labour would respectively be 3.3 and 2.2 seats worse off. The fallout is not just limited to those two parties either; the Greens, for example, would be 0.5 seats worse off. And who would form the government?

So if NZF takes votes off National and Labour equally and makes the 5% threshold there is a much reduced chance of National getting a majority, but we would still have a National Prime Minister. Winston Peters wouldn’t be in a position to force another election.

**What if the votes come exclusively from National?**

And what would happen if NZF just makes the 5% threshold, and takes their extra votes exclusively from current National supporters. We call this “Situation #2”. Under Situation #2 NZF would still win exactly 6 seats, and National would be as follows:

So if NZF takes votes solely off National and just makes the 5% threshold there is a much reduced chance of National getting a majority, but we would still most likely get a National Prime Minister, even without taking the Maori Party into consideration. Winston Peters almost certainly wouldn’t be in a position to force another election.

**What if NZF makes 7%, and the votes come exclusively from National?**

Now lets assume that NZF wins exactly 7% of the vote, with their extra votes coming exclusively from current National supporters. We call this “Situation #3”. Under Situation #3 the results would be as follows:

So even under the rediculously optimistic scenario of NZF doubling their current support in the next six days, with the new support coming solely off National, the Maori party would still most-likely hold the balance of power in parliament.

And what would the Maori party do? Coalition with National, ACT and United Future? Or coalition with Labour, Greens, Mana and New Zealand First? Even assuming that the latter four parties were all on the same page (unfeasible, given recent statements from their leaders), would the Maori party favour them? Not likely if a three-party right-wing coalition had a numbers advantage over the four-party left-wing coalition. It would be far too easy (politically) for the Maori Party to go into a right-wing coalition, and extract some fairly heavy concessions whilst doing so.

**Conclusion.**

So, in summary, even if NZF win 7% of the vote, which is unlikely on current polling, the chances of them holding a balance of power and forcing another election are effectively zero. Anybody who suggests otherwise is just being a bit hysterical.