Meka Whaitiri's defection 'small-fry' compared to losing Jacinda Ardern - Kelvin Davis

Labour deputy leader Kelvin Davis has brushed off the shock departure of Meka Whaitiri, calling it "small-fry" in comparison to losing Jacinda Ardern.

"We have a saying in Māori," he told Morning Report today, less than 24 hours after the Ikaroa-Rāwhiti MP's bombshell.

"It's basically, 'thank you, next'. We're just moving on."

Whaitiri has switched allegiances to Te Pāti Māori, the sudden move confounding her former Labour colleagues, opposition MPs and legal experts alike.

NZ First leader Winston Peters (not currently an MP) said Whatiri was "trampling" on the democratic process, specifically the waka-jumping law that was meant to prevent MPs from defecting from parties they were elected to represent, and getting to stay in Parliament.

The opposition has demanded to see the correspondence between Whaitiri and Speaker Adrian Rurawhe which led to his decision Whaitiri had not triggered the party-hopping rules, and was still allowed to remain in Parliament as an independent.

University of Otago law professor Andrew Geddis said the language Whaitiri used at a media conference on Wednesday morning announcing her decision was "unequivocal".

"I have officially notified the Speaker that I have resigned from the New Zealand Labour Party and have joined Te Pati Māori," were Whaitiri's words.

"But it later transpired she hadn't written to the Speaker in such unequivocal terms," Geddis told Morning Report. "Instead it appears she only told the Speaker, 'I'm not going to vote with Labour anymore and I want to sit somewhere else in the chamber'.

"The Speaker has made the determination that isn't enough to meet the requirements under the legislation… He seems to think under the legislation, you need to use specific magic words: 'I have quit my party' or 'I want to be an independent'."

Rurawhe said he followed the law "to the letter".

Labour could use its power under the law to kick her out of the party, Geddis said, but it had chosen not to. Prime Minister Chris Hipkins on Thursday morning said a byelection this close to the general election (in October) was not in anyone's interests.

"It would be extremely helpful if the Speaker would release the communication so that everybody could understand the events and the decision making that's gone on," ACT leader David Seymour told the House on Wednesday.

"He's clearly had correspondence with him, so he knows that that's what she wants to do, 'cause there's been some dialogue and back and forth between them," said National's Chris Bishop. "So that that's the puzzling element of all of this. It's a giant, giant mess."

Geddis agreed with opposition MPs that correspondence between Whaitiri and Rurawhe should be made public.

"It's a constitutional question, and I'm not sure it's enough for the Speaker to say, 'Trust me, I'm right'."

'Small-fry', not 'stardust'

Davis said once the news had sunk in, the Labour caucus did a "collective shrug".

"We're disappointed. None of us saw this coming. She was there amongst us, then suddenly she wasn't, so we were all taken by surprise. But as a party we just have to get on with things.

"We had Jacinda Ardern move on earlier this year, and we transitioned pretty seamlessly to Chris Hipkins … and this is - with all due respect to Meka - this is small-fry in comparison."

Whaitiri on Wednesday said she felt in shackles in Labour. Davis said that was "the sort of language you use when you don't have a real reason for leaving your party".

He compared it unfavourably to Te Pāti Māori founder Tariana Turia's reasons for leaving Labour, saying she had a "real principled stance".

"I'm not sure what Meka's principled stance is. I think she's just had a change of heart and decided to move on."

Hipkins found out about the defection on arrival in the UK, where he will be attending the king's coronation this weekend.

Despite attempts to contact Whaitiri, he still has not talked to her.

"I'm still not clear exactly what her reasoning or thinking was behind her decision to switch," he told RNZ. "Generally speaking, I'd expect that I would have at least received a phone call, so obviously I'm disappointed that that hasn't happened."

Davis said he told Hipkins it was all under control.

"I texted Chippy and said, 'No doubt your phone will be going off about Meka but we've got this covered and it will all be okay.'"

Debbie Ngarewa-Packer defiant

Te Pāti Māori co-leader Debbie Ngarewa-Packer told Morning Report she did not care what others had to say about the process.

"At the end of the day, I'm involved at this side of receiving a well-regarded, particularly here in Ikaroa-Rāwhiti, member of Parliament who wants to return to her whakapapa and be a part of Te Pāti Māori."

Despite the obvious electoral benefit Whaitiri brings to the party - being a high-profile incumbent in an election where Te Pāti Māori will likely need to win an electorate to return to Parliament - Ngarewa-Packer said it was Whaitiri who came to Te Pāti Māori, not the other way around.

"Te Pati Māori have always let our Māori caucus, those that are in the House, out of the House, know that we're an open-door movement for them. It's really come about because of Meka's calling, and obviously as we do at marae, we've received her and will continue for anyone…

"Did Rawiri (Waititi, co-leader) and I go and specifically knock on her door? No. This has been about Meka's awakening."

Ngarewa-Packer said she had been aware of the potential move for only about a week. Like Whaitiri, she could not cite any particular single reason for defecting from Labour, but insisted there was no "beef".

"I think it is a values thing… When you get a calling to belong to a movement that is upbeat, that is growing, that is relatable, and that not only yourself but your wider whānau - particularly your children - can relate to and want to be a part of, you just go."

She said she had confidence the Speaker handled the legal process correctly,

Last thing Ikaroa-Rāwhiti needs right now

Both Hipkins and Davis said the biggest losers in Whaitiri's move were the people of Ikaroa-Rāwhiti, struggling to bounce back from the carnage wrought by Cyclone Gabrielle.

"They've got some big challenges ahead of them and Meka Whaitiri as the minister responsible for leading there had a real opportunity to make a difference to the local community, and she's not going to be able to do a lot to support them in the next few months before the election when she was going to be the minister - or was the minister who was going to be able to do that. So that's disappointing," the Prime Minister said.

"But our focus now has to be on making sure that we are rallying around that community and providing them as much support as possible. I have 100 percent confidence in Keiran McAnulty, who's going to take on the leadership role in the lower part of their electorate, and Kiri Allan, who's already doing that role in the northern part of the electorate."

Davis was more succinct in his evaluation.

"The last thing they need is an MP who's going through a little crisis."