Mr Mallard will be demoted and stripped of important portfolios after throwing a punch he now admits was "one of the most stupid things I've ever done in my life".
The visibly distressed minister was taking "time out" yesterday after the scuffle over remarks made by Mr Henare in Parliament on Wednesday.
Mr Mallard and Mr Henare had to be pulled apart by a member of staff after Mr Mallard punched Mr Henare, apparently after the National MP grabbed him by the tie.
Mrs Turia said Mr Mallard's behaviour was unacceptable and should be punished.
"We in Parliament shouldn't be above the law. We are the lawmakers and as such the one thing the public should be able to expect from us is that we uphold the law," she said on Radio New Zealand.
"It is totally unacceptable particularly when right now we're spending $14 million on an anti-violence campaign which says we must say no to these things."
There should be no tolerance of violence, she said.
"The Maori Party has been very consistent with that message, that it does not matter where or how or why it occurs, we should have no tolerance to it."
She said Mr Mallard had a record of aggression in Parliament.
"His whole behaviour is extremely aggressive. People put up with that in the House. We kind of say it's all kind of robust debate being incredibly rude to other people and being aggressive, but it doesn't need to be that way."
Mrs Turia said Mr Mallard had been incredibly personal in his attacks over the years.
"Basically I said shut up and the last word I'll leave to everyone's imagination."
Mr Henare said it was not a swear word or a derogatory word. "It's obvious that it was was a word that peed him off immensely ... we had a bit of a heated discussion and then he tapped me one," Mr Mallard said.
Asked if what he said was similar to what Mr Mallard said about Don Brash last year, when he outed the former National leader over an alleged affair, Mr Henare said "could have been."
Mr Mallard sought to clear the air over his new relationship yesterday by confirming to The Dominion Post that he was romantically involved with former world champion rower Brenda Lawson.
The relationship started after Mr Mallard's marriage ended in June.
He said he was acting to put an end to persistent rumours that had wrongly identified a number of women, including staff members, as his new partner.
Mr Mallard apologised to Mr Henare and "left his fate" in the hands of Prime Minister Helen Clark - effectively an offer to resign.
Though he is unlikely to be sacked, Miss Clark is expected to demote him as a signal that his behaviour is unacceptable and he will be relegated to more junior portfolios when she reshuffles her Cabinet next week.
But groups including Family First are calling on him to step down, saying his actions are at odds with the Government's promotion of laws outlawing physical punishment.
Miss Clark said she was not offering excuses for Mr Mallard, but he had had "a lot of grief in his life in recent times".
His father died two weeks ago and his marriage broke up this year.
"He does need to take time out to come to terms with it. He can't work out why he did this."
Mr Henare said Mr Mallard had "lost his rag".
In a likely reference to Mr Mallard's role in outing former Brash's alleged affair, Dr Brash is understood to have texted Mr Henare yesterday saying: "Good on you Tau. The truth will come out about that bastard. Cheers Don."
Mr Mallard said there was no excuse for punching Mr Henare.
"It is one of the most stupid things I've done in my life and I really regret it ... I am a minister, I am 53 years old, I shouldn't be acting like a schoolkid."
National Party leader John Key said there was no place for violence in Parliament.
He said he was disappointed in Mr Henare but added that no further action would be taken against him.
- with NZPA
- The Dominion Post
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