Prime Minister Christopher Luxon has told Newstalk ZB there should "definitely" be a referendum on a four-year parliamentary term, and signalled he is open to also asking the public whether New Zealanders still want MMP as their electoral system.

Luxon said it was "quite right to check-in constitutionally" on whether MMP — the proportional voting system New Zealand has used since 1996 — remains the system voters want. The last time that question was put to the public was 2011, when 57.8 percent chose to keep MMP. RNZ

His comments caught his coalition partners by surprise and appeared to take his own National colleagues off-guard. Deputy leader Nicola Willis said she knew Luxon held those views on an MMP referendum and that they had been discussed in caucus and with New Zealanders. Justice Minister Paul Goldsmith said on Thursday it made sense to look at the four-year-term and MMP questions at the same time. RNZ

Reuters reported that a referendum on New Zealand's electoral system could be held as early as 2027 if Luxon wins the general election scheduled for November 7, 2026. In the same interview, Luxon reiterated his support for extending New Zealand's three-year parliamentary term to four years. Reuters

The government's four-year term push is not new. The Independent Electoral Review's final report, released in January 2024, recommended holding a referendum on the term of Parliament. The government agreed to introduce enabling legislation in February 2025, and the Constitution (Enabling a 4-Year Term) Amendment Bill passed its first reading in March 2025. The government then set that work aside, citing time constraints and a desire to prioritise law and order policies. Beehive

University of Otago law professor Andrew Geddis warned against holding an MMP referendum at the same time as a four-year-term referendum. Combining the two questions would confuse matters and undermine the validity of the referendum and its process, he argued. The electoral-system question should be dealt with first, before the question of parliamentary term length. RNZ

Geddis also said it remained unclear what the alternative to MMP would be, and described Luxon's apparent openness to a combined referendum as "a little bit of a brain explosion" following the problems of the previous couple of weeks. RNZ

The broader context here is one of constitutional process being raised through media interviews rather than through a structured policy rollout. Luxon's MMP comments were not accompanied by a Cabinet paper, a terms-of-reference document, or a published timeline. The four-year-term legislation already before Parliament had been parked by the government itself, making the revival of referendum talk on both matters a departure from the government's own stated sequencing.

Geddis's objection to combining the two referendums rests on a straightforward point: a voter asked to decide at the same time whether to keep MMP and whether to extend the parliamentary term faces two distinct constitutional questions with different implications. A four-year term under MMP raises different accountability considerations than a four-year term under, say, a supplementary member or first-past-the-post system. Running both questions on the same ballot risks conflating the outcome of one with the other.

Think of it this way: it is like being asked in a single vote whether to renovate your house and whether to change architects. The answer to one could well depend on the answer to the other, but putting them on the same form makes it hard to tell which decision drove the result.

For the coalition, the practical problem is political alignment. ACT and New Zealand First have their own histories with electoral reform and MMP in particular. Luxon's comments on Newstalk ZB did not appear to have been cleared through the standard coalition channels before delivery. Willis's response, framing the views as previously discussed in caucus, does some work to close that gap but does not address whether coalition partners were consulted before the Prime Minister went public.

The 2026 election is now three months away. A referendum at the 2027 timeline reported by Reuters would require legislation to be drafted, introduced, and passed through Parliament, with the Electoral Commission given enough lead time to design and test the ballot question or questions. The government set aside its four-year-term referendum legislation citing time constraints the first time. Whether it can or will revive that work, and add an MMP question to it, is not yet established.

What is established is that the Prime Minister has put both questions on the public agenda in an election cycle where they were not previously expected to feature, and that the constitutional experts closest to the issue are urging caution about the approach he has signalled.