New Zealand First is reviewing its donation practices as the Serious Fraud Office (SFO) decides whether to probe allegations it's been hiding donations in a slush fund.
Prime Minister Jacinda Ardern now wants a full independent look at political donation laws, and she's refusing to say whether she trusts New Zealand First leader Winston Peters.
Peters shut out questions about his party's donations and refused to even make eye contact with Newshub when he was approached in Parliament on Monday.
Instead, he left questions to the Prime Minister to answer during her post-Cabinet press conference.
But Jacinda Ardern couldn't express trust in her Deputy Prime Minister. When Newshub asked if she trusted Peters, she wouldn't say "yes" or "no" instead replying, "We have an excellent working relationship".
Ardern was asked three times but never once said yes she trusts him.
As for whether the Prime Minister will stand Peters down if the SFO decides to investigate, Ardern said she will not get into hypotheticals.
It follows reports last year from Stuff that the New Zealand First foundation was a slush fund which received more than half a million dollars in donations.
Money was allegedly spent on party expenses like the party HQ, hiring boxer Joseph Parker for a party conference and legal advice for an MP.
Peters has repeatedly denied the claims labelling them "fake news".
It's the second case relating to political donations that have come across the SFO's desk recently and less than two weeks ago it laid charges over National Party donations - neither Simon Bridges nor National is among those charged.
The Prime Minister now wants an independent review of donation laws
"It is more than likely to happen after the election but it's the right thing to do," Ardern said.
The Electoral Commission initially looked into the New Zealand First allegations and on Monday said it formed the view that the foundation received donations which should have been treated as party donations.
"The donations were not properly transmitted to the Party and not disclosed as required under the law."
Because the commission is legally toothless, it referred to the matter to the police, forcing the Prime Minister to pull Peters aside for a 'please explain'.
"He himself has sought assurances of the New Zealand First Foundation around correct conduct," Ardern said.
The foundation's trustees are Peters' close mate and lawyer Brian Henry and former New Zealand First MP Doug Woolerton.
Neither would provide comment to Newshub.
Political Editor Tova O'Brien's analysis
We may not know until next week if the SFO will actually investigate these allegations.
Ironically, Winston Peters could be helped politically by the fact National has just been through an SFO investigation itself.
Neither Simon Bridges nor the party are among those charged, but no one stood down during the investigation - setting a kind of precedent.
Peters is also attempting to front foot this by reviewing his parties donation processes.
But remember back in 2008, NZ First didn't make it back into Parliament that election.
So, it will all come down to what voters decide come September 19 - and that's anyone's guess.