How leadership challenges happen in New Zealand politics

Explainer - 'Tis the season for political speculation, as pundits attempt to predict the future of National and Labour party leaders.

What happens when political parties decide it's time to launch a challenge against their leadership? As one expert describes, it can trigger a "Shakespearean" battle for power.

To be clear, there's been absolutely no sign there will be a leadership change for National or Labour at this moment in time.

But persistent murmurs about Prime Minister Christopher Luxon's leadership have increased in recent weeks, with senior MP Chris Bishop having to deny he was plotting to roll Luxon, while the Sunday Star-Times on the weekend featured a story by national affairs editor Andrea Vance calling recent actions by Bishop a "failed coup".

Luxon's poll rating as preferred prime minister was under 20 percent in September's RNZ/Reid poll and the government's performance rating hit a new low in the recent IPSOS Issues Survey.

But does that all actually add up to a possible leadership challenge before next year's election?

New Zealand history is filled with dramatic moments when confidence in a party leader has dropped and a leadership challenge is held. They've even happened to sitting prime ministers.

Here's how leadership challenges tend to work.

How does a leadership change happen?

It's as simple as a member of the party caucus calling for a no-confidence vote in its leader. If the party heads up the government, that could mean a change in prime minister if the vote succeeds.

For the National Party, it's a straightforward majority rule vote by the party's MPs.

"Formally, in the case of the National Party the decision rests with the caucus (which the party's constitution refers to as the 'Parliamentary Section'), which can move at any time to replace the leader (who must then be approved by the board)," Massey University professor of politics Richard Shaw said.

The Labour Party caucus also can directly vote for its new leaders, but if it doesn't make a decision within seven days, it gets turned over to their electoral college - a combination of the caucus, party members and unions - to decide.

Prospective leaders must also get a two-thirds majority in the Labour caucus vote, or it's also off to the electoral college.

The caucus room vote totals in leadership elections are generally not made public.

"Any member of caucus could go to a caucus meeting and in theory give notice that they'd like to move that the caucus has no confidence in a leader," said Chris Eichbaum, adjunct professor at the School of Government at Te Herenga Waka-Victoria University of Wellington.

"If you were in a splendid isolation of one that wouldn't last long," however, he noted.

A successful leadership challenge is all about building up the votes.

This process can play out in the media - witness how many columns and hot takes have been published in the past few months speculating about the prospects of Chris Bishop, Education Minister Erica Stanford or Finance Minister Nicola Willis - but it also plays out behind the scenes at Parliament, said Eichbaum.

"It is incredibly Shakespearean - it is covert, it's behind the scenes, there's speculation, and then something will happen to turn speculation into substance. And if it's a serious challenge, that's where people start doing the numbers.

"It tends to be part of the choreography of it that once it becomes known that there is a move afoot to unseat then essentially it's a matter of the candidates, the incumbent and the challenger sort of doing the votes.

"... One of his allies or it could even be one of the party whips, they may present the prime minister with a list saying: 'Prime minister, you simply don't have the votes.'"

Has a sitting prime minister ever been rolled?

Several New Zealand prime ministers have resigned after facing leadership challenges, although the last time it happened was nearly 30 years ago when Jenny Shipley mounted a challenge against the late Prime Minister Jim Bolger in 1997. Bolger resigned before a vote was taken, a tactic which has generally proven to be the case instead of prime ministers being forced out by a vote.

Other prime ministers in relatively recent times who stepped down include Sir Geoffrey Palmer, who resigned and was replaced by Mike Moore prior to the 1990 election, or David Lange who resigned in 1988 after unsuccessful challenges to his leadership.

Eichbaum worked in the Beehive as an executive assistant at the time that Sir Geoffrey faced a challenge by his Cabinet, and then went on to work as a senior advisor for Helen Clark.

"Palmer went about six weeks out from the 1990 election," he said. "But the issue was never taken to the caucus - where he may well have enjoyed majority support - because essentially, reflecting polling that indicated some Cabinet members were at risk of losing their seats, he was told that he didn't enjoy the confidence of his cabinet or sufficient of them. His erstwhile senior colleague Mike Moore made no secret of his willingness to assume the role."

And then there's leaders who stood down after losing an election like Helen Clark, or resigned for other reasons like Sir John Key and Dame Jacinda Ardern.

"Clark stepped aside because she had lost an election, and Key and Ardern left because they had calculated that their parties stood a better chance of the next election without them," Shaw said.

"A leadership change can occur for all sorts of reasons, some of which are internal to a political party and its sense of momentum and/or the need for a new sense of energy and direction."

Luxon isn't the only party leader who has been subject to leadership speculation.

Former Prime Minister Chris Hipkins has remained Labour's leader after losing the 2023 election and made no indication he plans to leave before next year's election, although there has still been media speculation about what a change at the top might mean for Labour's chances.

Of course, there have been heaps of leadership changes to parties outside government - the National Party went through a run of four leaders after Key resigned in 2016 until Luxon became leader in 2021, including Todd Muller's mere 53 days at the helm, while Labour also went through four leaders between Clark and Ardern.

Do different parties have different rules?

There's no overall guideline for leadership challenges in New Zealand politics, which are left to parties to set the rules.

For instance, the Green Party allows leadership challenges to be put forward by party delegates, such as a series of unsuccessful challenges in 2021 and 2022 to former co-leader James Shaw's co-leadership.

The Labour Party has changed how it allows votes a few times, and from 2012 to 2021 it allowed party members, the caucus and unions to decide every leadership vote. That could result in clashing priorities, as with 2014's leadership election, Eichbaum said.

"The most recent case involved Andrew Little and Grant Robertson, where the MPs' preferred candidate was not the person that became the party leader.

"That was the case with Grant Robertson who was preferred by his caucus but because the broader party had basically a vote in the proceedings by dint of the arrangements they have, Andrew Little was able to come in over the top."

Of course, facing grim polling, Little himself stepped down in 2017 just seven weeks before an election, and Deputy Leader Ardern went on to become New Zealand's 40th prime minister.

What can trigger a leadership change? Is it just about the polls?

Parties can roll their leaders in disagreements over policy, and it's been known to happen.

"Polling/public sentiment can, of course, be major drivers, but there have also been instances - and I think the 1996-1998 National/NZ First government was a case in point - in a party where a caucus and a cabinet will feel that a change is due regardless of the public's views," Shaw said.

But these days, a lot is still driven by how they're doing in the polls. Blame the influence of American presidential-style politics and the increasing spotlight shown on leadership - polls now typically include preferred party vote side-by-side with preferred prime minister picks.

"It's polling twinned with a presidentialisation of politics," Eichbaum said. "Leadership has always been important, but it's been elevated now.

"Because of the frequency of polling around leadership, the nature of the polling going into the attributes of the leader just becomes much, much more salient. There's a machine out there and the raw material is what we think about a leader."

But polls still aren't the only factor, Shaw said.

"While polling and public sentiment are clearly important, there are institutional filters - including the party organisation, caucus and cabinet - which mean that the line from opinion polls to a leadership change is neither straight nor straightforward."

While being removed as leader could be seen as humiliating, Eichbaum said leaders often have a fair bit of leverage in the process.

"There's an element of decorum and dignity quite often which is unusual in politics. At times, they say: 'Okay, what's in the best interest in the party in this situation?'

"He or she may well say 'All right, I will resign, but I want these things to occur,'" he said.

Leaders could also be heavily involved in tapping their preferred successor, such as when Sir Bill English replaced Key.

How a prime minister manages their caucus - particularly if it's large - also matters. Every vote counts in a leadership race, whether it's a senior MP or an obscure back-bencher.

One of the roles of a prime minister is "basic HR," Eichbaum said.

"A very, very good prime minister will make a point of staying very close to his or her caucus and also meeting with backbenchers on a regular basis."

Luxon told reporters recently he had "no concerns" for those National MPs who could lose their jobs on current polling, explaining he was confident all its MPs would return after the election.

Still, fears for marginal seats or list MPs can also play a role in being rolled. "If you're one of those (at-risk) MPs, how do you feel?" Eichbaum asked, describing the "creeping incremental insecurity" that has emerged to fuel previous challenges.

What happens if the government is a coalition and the leader is rolled?

The nature of a coalition requires cooperation. In the 1996-1998 National/NZ First government, the coalition crumbled in 1998 when Prime Minister Jenny Shipley sacked Winston Peters from cabinet. Peters and NZ First had gone into government with Bolger, who was rolled by Shipley. Only a small group of independent MPs held the government together until the 1999 election.

"The interesting thing about what happened with Bolger, and I think this raises issues in the current context, is how its coalition partner reacted to Bolger being rolled," Shaw said. "I don't recall there being a significant public outcry, but there certainly was a significant response from NZF."

The current three-headed Coalition of NZ First, ACT and the National Party could also create issues if Luxon were replaced.

"Hypothetically, therefore, were the National Party to seriously entertain removing Luxon as party leader, the fact that he is also the prime minister gives the ACT and NZF parties some stake in the issue as well," Shaw said.

"In other words, in cases of coalition government the issue of the party leader is necessarily an issue for the government's constituent partners.

"Any destabilisation of a coalition government's major player, it's going to be of deep interest to the coalition's minor players."

Don't the public get any say in these things?

We elect our local electorate MPs and choose our preferred party when we vote, but the public doesn't get to choose what might happen inside the Beehive after Election Day.

Still, how the public may react to leadership changes is key.

"The optics of these things are also important and that's a consideration," Eichbaum said.

For instance, Australia went through five prime ministers in 10 years in a series of leadership spills creating what was called "a decade of disposable prime ministers."

"Is the party going to get a bump in the polls as a result of a person going? What's it doing to the perception or the perception of the party as the kind of viable governing force if we are seen as a house divided against itself and we can't hold on to a prime minister?"

And of course, there's also this factoid - any time in the past 50 years or so that a prime minister has resigned mid-term, their party has gone on to lose the next general election.

Eichbaum said current talk about leadership challenges is largely fuelled by the media, but in the end, it really all comes down to what happens inside party caucuses.

"A very well-executed leadership spill of course - this is where Shakespeare comes back in - you know, you're not going to see it coming."

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