The five people convicted on Friday for the manslaughter of Janet Moses escaped jail because they were Maori, Labour MP Trevor Mallard says.
In the High Court at Wellington, Justice Simon France imposed community sentences on the five for their roles in the curse-lifting ceremony which killed the 22-year-old mother of two.
Ms Moses drowned as water was forced into her eyes in an attempt to flush out demons.
The ceremony took place in 2007 at a small Wainuiomata flat, crammed with more than 30 whanau members.
Mr Mallard, MP for Hutt South and a Wainuiomata resident, made the claim on Labour Party blog site Red Alert.
"The fact that they weren't sent to prison because they are Maori just doesn't seem right to me," he wrote.
"I accept that they almost certainly would not reoffend and prison may be an expensive waste of time. And there are too many Maori in prison.
"But I am certain that a Pakeha exorcism that resulted in torture and death would result in a prison term - albeit not necessarily a long one."
Speaking on Radio New Zealand this morning, Mr Mallard acknowledged it was not normal for an MP to comment on sentencings .
"It is a very unusual set of circumstances and I think in this case the judge got it wrong," he said.
"I think there is a lot of sympathy for the individuals involved. They did get caught up in some sort of hysteria. They were sleep deprived.
"But there's just not an acceptance either from the vast majority of Maori or Pakeha people that you can effectively torture someone for well over a day...causing death, and there not be a jail sentence."
Mr Mallard stressed he did not want to be seen as putting pressure on Solicitor General David Collins QC to appeal the sentence.
He said it was, on the whole, not desirable for MPs to begin voicing their opinions on court cases.
"It wouldn't be (good) and you can't have people second guessing judges all the time. Clearly this is exceptional.
"If I was a minister, for example, part of the executive, it would have been less likely and less appropriate for me to do it.
"But I am a representative of my community and I think people shouldn't hide away views like this."
Mr Mallard said he was against a separate judicial system for Maori and encouraged discussion which could lead to better understanding of issues.
"I do think we've got to have one system for one country. There can on occasion be sentences that are mitigated by particular circumstances.
"But I think you've got to do that on a rational, planned sentencing council-type basis rather than an ad-hoc decision to give a particular group what is seen to be and what is actually a very, very lenient sentence, probably based on their ethnicity." Mr Mallard was not alone in his criticism of the sentence. Prominent defence lawyer Barry Hart said last week the judge had been too lenient.
"It doesn't matter how you look at it, the sentences are really light," he told the Dominion Post.
Crown Law said it was too early to consider an appeal.
Prime Minister John Key said while he did not condone the actions of Ms Moses' killers, he believed they were "truly misguided but not malicious".
"If the judge really believed that they didn't go in there with the intent to kill, if they went in there because they truly in their hearts believed the person was possessed, then I'm not sure locking them up would achieve a lot.
"I'm all in favour of putting people in prison...but that's if they're a danger to society," he told NewstalkZB.
NZPA
Trevor Mallard speaks to Maggie Barry on RadioLIVE.