Green Party co-leader Chloe Swarbrick expects the Speaker of the House to move efficiently to decide Darleen Tana's political future.
The Green Party's membership reached unanimous consensus on Thursday night to use the "waka-jumping" legislation to kick Tana out of Parliament.
Tana quit the party in July amid allegations of migrant exploitation at her husband's bicycle business.
The final decision would sit with Speaker of the House Gerry Brownlee.
Greens co-leader Chlöe Swarbrick on vote to kick Darleen Tana out of Parliament
Swarbrick told Morning Report they had written "one final time" to Tana, to provide her with a final opportunity to "do the honourable thing and finally accept our request for her resignation as a Member of Parliament".
They had not yet received a response from Tana, she said.
"Not that I am aware of this morning, no."
Swarbrick said she hoped the process to remove Tana from Parliament would happen "efficiently and in line with the law", but would not be drawn on how long that might take, instead directing host Corin Dann's question to the Speaker's office.
Dann asked Swarbrick if the Speaker might raise questions about the proportionality of Parliament with Tana's departure.
The High Court ruling had found the process the Green Party took had been fair, reasonable and legally authorised, and Tana resigned from the Green Party voluntarily, she said.
The judgement included a reflection on the fact that her doing so affected that proportionality.
"That ... has impacted obviously not only in terms of our resourcing, and the shrinking of the literal size of our caucus from the 15 members we received as a result of the 330,000 New Zealanders who voted for us, for our principles and our policies at the most recent election - but also in terms of the proportionality of the House, in terms of our votes."
Swarbrick noted that Tana had not been present to vote on certain legislation.
However, Dann pointed out that her absence meant she had not voted against Green Party policy, so that did not affect proportionality.
This was one of many "very hyper-technical legalities", Swarbrick said, but the party still believed it had affected the number of votes.
Responding to criticism that the Greens had initially opposed the "party-hopping" legislation, only to deploy it later against Tana, Swarbrick said they would be criticised regardless.
"I've heard every single iteration of it, I think, over the last few months."
Their move to expel Tana from the party had not been taken lightly, she added.
"In the Greens, we are ... acutely aware of our history and we spent a really long time deliberating on those things.
"We had a very thorough discussion with representatives from different parts of our party last night, including former leadership, and we worked through those historical concerns, which ... effectively boil down to two things.
"I can promise you I have personally, earnestly, mulled this over many, many times."
Their concerns around the "party-hopping" law included the potential for power to be concentrated in one person's hands, such as a leader, taking "the small, dictatorial approach to things".
But the Green Party had gone "far above and beyond" the law to ensure its membership was consulted, "before coming to that point of full consensus".
Another concern raised was the potential for an MP to be ejected from a party when they were making a stand on their principles, she said.
But anyone who had read the executive summary of the inquiry into Tana's behaviour would conclude that her stand was not based on principles.
"This is not a principled stance - but unfortunately, quite the opposite."
Former Green MP Metiria Turei was present in the meeting and her kōrero at Thursday's was "deeply meaningful", because her words provided some context of statements that had been made in the past, as well as the importance of making a principled decision in light of the available evidence, Swarbrick said.
"That's what it looks like to grapple with complexity and come through the other side as a far stronger democratic force and I'm really, really proud of our party for that work."
Dann pointed out it had been a difficult year for the Green Party.
Swarbrick said MPs across Parliament had expressed solidarity with her, and shared similar experiences within their own parties.
"I'm really proud of the fact that we have done everything that we possibly can, with the things we have control over, with our values as our guiding star."
She described the passing of Efeso Collins - who died during a charity run earlier this year - as a "trauma" .
"We've literally lost a friend and a colleague and a community leader... it's been incredibly trying, and incredibly challenging, but ... when we look back on this year as the Green Party, we will see that we have genuinely been forged in fire."
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