National has called for the resignation of Speaker Mallard this week, accusing him a gross abuse of power, while Mallard was in the chair.
Leader Judith Collins has also stepped up National's campaign against Mallard, saying he is a bully, a disgrace and unfit for the job.
Collins wrote to Prime Minister Jacinda Ardern last week about Mallard after receiving court documents related to a defamation case Mallard has settled with an apology and payout for accusing a former parliamentary staffer of rape.
The cost to the taxpayer has been about $333,000.
Newstalk ZB Political editor Barry Soper told Heather du Plessis-Allan it speaks volumes about the Prime Minister.
"Jacinda Ardern may like to preach kindness from the pulpit of truth, she does this all the time.
But she is selectively kind. That has been shown with Trevor Mallard, and the little regard shown to the man falsely accused of rape by him."