Jacinda Ardern is being accused of having one rule for her own ministers and another for New Zealand First.
Newshub claims Kris Faafoi made promises to long-time friend, musician Jason Kerrison, to help with an immigration case.
He allegedly offered to help speed things up, but reportedly told Kerrison he couldn't put anything in writing.
Political commentator Matthew Hooton told Mike Hosking the Prime Minister is responding swiftly, something she didn't do with the New Zealand First Foundation saga.
"We're being told that the Prime Minister is taking this seriously, she's personally launched a investigation into it all, but only when it's a Labour Minister.
"When it's a NZ First Minister, she says it has nothing to do with her. It just so happens that Kris Faafoi is one of the few competent ministers in her government."
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