Commentary: Deliberately trying to engineer an overhang is a form of electoral cheating, argues Professor Andrew Geddis, of the Faculty of Law.
Generally speaking, it’s not a healthy sign for a country’s democracy when the last week of an election campaign is dominated by discussion of how best to exploit the electoral rules to enable a particular group of parties to retain power without obtaining majority support from the voters.
And yet here we are, anxiously parsing the intricacies of vote splitting, seat allocations, and parliamentary overhangs rather than how best to respond to our cost of living crisis, the looming superannuation cliff, and the challenges of climate change.
Not that this is a particularly new issue. In August, warnings were being sounded over Te Pāti Māori’s call for its supporters to engineer a parliamentary overhang by only voting for their electorate candidates. In a political version of Newton’s third law of motion, this strategy galvanised some deep-pocketed enthusiasts on the right to propose their own version whereby National’s party vote gets strip mined to feed Act and New Zealand First while leaving its electorate MPs to form a parliamentary overhang.
To which we may shrug and think: “So far, so standard – people are proposing electoral tactics to increase the chances of ‘their’ side winning. And if both sides are doing it, then how wrong can it be?”
Well, pretty wrong. In fact, so wrong that it threatens to undermine what MMP as a voting system is meant to provide, and what electoral democracy as a whole is understood to deliver for Aotearoa New Zealand.
Under MMP, you get two votes: electorate and party. The electorate vote allows you to choose the individual you think will best represent your area in Parliament and as a local representative. David Seymour summed this up pretty well as voting for the person you most trust to take your call as a constituent on a late Friday afternoon.
That person might not be cut from the same ideological cloth as you. However, it won’t really matter if you help to elect them as an MP for a party that you don’t support. That’s because after an election a party’s seats get filled first by its successful electorate candidates, with list seats then given to “top up” that party’s share in Parliament until it’s in line with its share of the party vote. All you’re doing by helping this candidate get elected is giving their party an electorate MP rather than a list MP.
What should matter for the overall share of party representation in Parliament is how you cast your party vote. It’s this vote that is intended to determine the total number of seats each party gets, and thus how big a role it can (maybe) play in a future government. As such, you ought to be casting this vote for the party you most support in an effort to maximise its presence in Parliament.
However, the various current vote splitting proposals reverse the purpose of each vote. They call on you to cast your electorate vote for the candidate from the party you most support, irrespective of what you actually think of that person as an individual. And then you must cast your party vote for a different party you don’t really support in an effort to help that party maximise its presence in Parliament. The reason behind both votes is thereby corrupted, meaning that our MMP system will fail to deliver representation in the way it is designed to.
Of course, the purported justification for misusing each vote is purely tactical. If doing this can generate a parliamentary overhang for one party, while helping other allied parties win more seats through an increased party vote, then it gives that combined bloc of parties an advantage over the other. But recognise the basis on which it is doing so.
A parliamentary overhang is a distortion of proportionality; or, in simpler words, it gives a party more presence and potential power in Parliament than it should have based on its support from voters as a party. Deliberately trying to engineer an overhang is, in even more simple words, a form of electoral cheating.
This electoral cheating might then determine the overall election outcome, in terms of which bloc of parties gets to form the next government. However, successful cheating is still cheating, in that any government formed would exist only because of a calculated effort to confect a parliamentary majority without actually having majority support from the voters.
Indeed, the aim of this tactic is to produce a parliamentary majority for one bloc of parties even though it receives fewer votes than the other bloc of parties. Which is a complete reversal of how democratic government is supposed to operate in Aotearoa New Zealand.
What about the claim that as manufacturing an overhang is within the electoral rules then it’s a legitimate tactic? Well, there’s a relevant cultural reference available to us to test the claim that if something is lawful then it should also be acceptable. In a deciding ODI cricket match in 1981, Trevor Chappell delivered the last ball of the New Zealand innings underarm so as to stop any chance of it being hit for six and so tying the match.
Perfectly within the rules. Probably seemed tactically clever. But regarded at the time as being such an outrageous breach of the very basis of cricket that its laws were changed to stop it ever happening again, while the incident remains shorthand for behaving in an unacceptably and shamefully wrong fashion.
And that was, in the end, only a game. When we’re choosing who may govern us for the next three years things matter so, so much more. Which is why cheating at this, even if its legal cheating, should never be accepted.
This piece first appeared on Newsroom 3 November, 2026.