Which brings us to the second quirk: that bizarre byelection. When a candidate died after nominations closed but before election day, electoral law required cancelling the electorate contest and holding it separately weeks later.

Port Waikato voters cast party votes on October 14 but could not vote for their local MP until November 25. This arose from rules designed for First-Past-The-Post that make little sense under MMP, where the party vote determines Government formation.

The third problem was the three-week delay in finalising results. Over 600,000 special votes (20% of all votes cast) required extensive verification before counting. Election night gave provisional results, but the official outcome was not declared until November 3. Extended uncertainty about the final seat tally and delays to coalition negotiations until there was certainty created an unnecessarily long period of policy limbo.

My report addresses these issues while proposing broader reforms to enhance MMP’s effectiveness.

The overhang problem particularly matters because it distorts the proportional representation that MMP promises. When Parliament expands unexpectedly, it creates uncertainty and undermines the system’s core principle that each party’s seats should match its vote share.

My solution is to abolish overhang seats entirely, as Germany did in 2023 after overhangs inflated its Parliament to 736 members. But rather than leave electorates unfilled, as in Germany, we would not make the current ad hoc additions to list seats.

Instead, we would shift the current 60:40 split between electorate and list MPs to 50:50. Increasing the pool of top-up list seats should substantially reduce overhang risk while giving major parties greater flexibility to inject talent through their lists.

However, implementing a 50:50 split within the current 120-seat Parliament would require reducing electorates from 72 to 60, making their geographic areas and populations much larger. This drives the case for expanding Parliament to 170 MPs, close to those of successful European countries with populations close to ours, like Norway (169), Ireland (174), Denmark (179) and Finland (200).

A larger Parliament is controversial, but it would deliver important benefits. The average population per seat would be back to where it was when MMP came in, making electorates smaller and easier to service. More backbenchers could be dedicated to specific select committees, without being spread thinly as is currently the case. This would improve legislative scrutiny and better balance an executive that has grown far too large.

New Zealand has 81 ministerial portfolios across 28 ministers and 43 departments. This bloat creates inefficiencies and fragmentation increases costs. Housing policy spans at least six ministerial responsibilities. The Ministry of Business, Innovation and Employment (MBIE) reports to 20 different ministers. When businesses need policy decisions or regulatory clarity, it is often unclear who to approach.

Consolidating to 15 ministers supported by 10 junior ministers would create clearer accountability while offsetting the cost of a larger Parliament. Importantly, it would establish clearer decision-making pathways that businesses could navigate more efficiently.

The report also recommends reducing the party vote threshold from 5% to either 4% or 3.5%, as recommended by the 2023 review of the electoral system. Our current threshold is moderately high by international standards, with many countries operating thresholds of 3% or 4%. A lower threshold would reduce wasted votes and give new parties with fresh policy ideas more realistic chances of representation.

“Coat-tailing”, the rule allowing parties that win an electorate to gain list seats even if below the threshold, should be retained. Coat-tailing significantly reduces excluded (or “wasted”) votes – those that do not count when parties fail to meet the 5% threshold or win an electorate seat.

Meanwhile, the report’s advocacy for a four-year parliamentary term would improve the ability for Governments to advance policy and legislation in a steadier, less rushed manner.

The report also proposes replacing byelections with party list appointments. This would maintain proportionality while avoiding costly, low-turnout byelections. And it recommends relaxing election-day advertising restrictions to allow individual political discussion.

These reforms address specific flaws while tackling broader, systemic issues. The benefits are clear: more predictable parliamentary arithmetic, better legislative scrutiny, clearer ministerial accountability and reduced policy uncertainty. And, ultimately, a stronger economy.

After 30 years, we have enough experience with MMP to identify flaws and improvements. It is time to make them happen.

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