Dr Mai Chen: Taming MMP – Tompkins Wake Public Lecture 2025

Friday 6 June, 2025

On 5 June 2025, Tompkins Wake and Te Piringa – Faculty of Law hosted their fifth joint Annual Public Lecture, delivered by leading public and constitutional law expert Dr Mai Chen at the University of Waikato's Tauranga campus.

Dr Chen's lecture, "The taming of MMP by the formation of a true coalition government: Impact on Policy/Lawmaking and the Courts in Superdiverse NZ," examined how the first genuine three-party coalition under MMP is reshaping policy development, lawmaking and the courts' supervisory role. She explored the tension between Parliamentary sovereignty, executive decision-making and judicial oversight, and what a more culturally and linguistically diverse New Zealand means for the future of the country's unwritten constitution.

• An expanded written version of the lecture was subsequently published in the July 2025 edition of the New Zealand Law Journal.

Background

Since 2021, Tompkins Wake and the University of Waikato's Te Piringa Faculty of Law have jointly hosted an Annual Public Lecture to promote public understanding of the rule of law. The 2025 lecture, held as a hybrid in-person and online event, marked the fifth instalment of the series and featured Dr Mai Chen, a barrister at Public Law Toolbox Chambers, co-founder of Chen Palmer (New Zealand's first public law specialist firm), and Chair of the Superdiversity Institute for Law, Policy and Business. Dr Chen holds a first-class honours degree from Otago University and a Master of Laws from Harvard, and is the author of The Public Law Toolbox, among other works on constitutional and administrative law.

What the Lecture Covered

Dr Chen's lecture addressed the practical and constitutional consequences of the coalition government formed in November 2023 between National, ACT and New Zealand First — described as the first "true" coalition of its kind under MMP. Drawing on her direct experience advising on policy and legislative processes, she examined how coalition dynamics are changing the way policy is developed and law is made, and what this means for the courts when reviewing executive action.

A central theme was the distinction between conduct that is "unconstitutional" and conduct that is "unlawful" — a distinction Dr Chen argued is becoming increasingly important as coalition negotiations produce policy compromises that test the boundaries of long-standing constitutional convention without necessarily breaching any statute. She considered how Parliamentary sovereignty, executive discretion and judicial oversight interact under these conditions, and whether the current political environment strengthens the case for a supreme, written constitution in New Zealand.

Dr Chen also addressed the challenge of making an unwritten constitution — including the rule of law and the Treaty of Waitangi — understandable and accessible to an increasingly superdiverse population. She noted that more than 30 percent of New Zealanders now identify as superdiverse, meaning they were not born in New Zealand, and argued that constitutional literacy matters more, not less, as that population grows.

For boards and public sector leaders. Coalition government changes the pace and shape of policy signals. Understanding the difference between a politically contested policy and one that is legally vulnerable helps organisations calibrate risk when planning for regulatory or legislative change.

For in-house counsel and public law practitioners. Dr Chen's coalface perspective on how coalition agreements translate into legislative drafting and executive action is directly relevant to advice on judicial review prospects, particularly where policy has shifted quickly following coalition negotiations rather than through orthodox select committee process.

The lecture continues a five-year partnership bringing senior constitutional and public law thinking to a regional audience, reinforcing Tauranga's standing as a genuine centre for legal education and public discourse.

Actions Checklist

• Public sector and regulatory teams: consider how coalition-driven policy shifts may affect the durability of current settings.
• In-house counsel: revisit judicial review risk assessments where policy has moved quickly through coalition negotiation rather than conventional process.
• Interested readers: read Dr Chen's expanded written lecture in the July 2025 New Zealand Law Journal, alongside her related submission on the Regulatory Standards Bill.
• Subscribe to TW's public law insights for further commentary on constitutional and administrative law developments.

Dr Chen's lecture offered a rare "view from the coalface" on how coalition government is testing New Zealand's constitutional conventions in real time. Her central message, that the gap between "unconstitutional" and "unlawful" is where much of the real risk and real debate now sits, is a useful frame for anyone advising on, or affected by, fast-moving policy change. Tompkins Wake was proud to continue its partnership with Te Piringa Faculty of Law in bringing this level of public law expertise to the Bay of Plenty.

This publication is for general information only and is not legal advice. Seek specific advice for your situation.