WARRIOR CHIEF: A watercolour picture of Ngati Toa chief Te Rauparaha. Thought to be copy after Isaac Coates. Reference: A-114-047

Despite being over-represented in New Zealand's criminal fraternity and prison population, Maori do not have a "warrior gene" that makes them violent, new research shows.

Scientist Gary Hook's review, Warrior Genes and the Disease of Being Maori, challenges the idea that Maori are genetically wired to commit acts of violence.

Three years ago, researchers Rod Lea and Geoffrey Chambers said high criminality among Maori was due to the monoamine oxidase, or "warrior", gene.

But Dr Hook said there was evidence they had made several serious flaws in their scientific reasoning.

Not only was the science criticised, but the ethics of claiming "genetic explanation for negative social and health statistics" had been questioned, he said.

"While conviction rates for domestic violence of Maori exceed those of any other group there is no indication that the (monoamine oxidase gene) system carried by Maori functions any differently from that of any other ethnic group and certainly no evidence to indicate that it was anything to do with violent behaviour in Maori."

Blaming domestic violence on genes simplified the problem and laid the blame on Maori themselves, Dr Hook said.

Racial stereotyping, particularly by scientists, was "unethical and scandalous", he said.

"Inter-group bias is recognised as an important influence on social behaviour.

"Maori are not borderline psychotics, retarded, hyper aggressive, depressive, antisocial, impulsive, suicidal risk takers and to suggest otherwise is irresponsible and not supported by the facts."

Maori nature was not the reason for high criminality rates, he said.

Perhaps it was because of victimisation during 160 years of colonisation or an "Eurocentric" justice system, Dr Hook said.

Maori Party co-leader Tariana Turia welcomed Dr Hook's review and expressed her disappointment at Dr Lea's and Dr Chambers' original research.

"I'm disappointed that two reputed scientists have done a disservice to a vulnerable part of our society and science by claiming they have come up with a breakthrough when all they have really done is make our job of finding solutions even harder."

The Government, communities and whanau need solutions not reinforcement of stereotypes, Mrs Turia said.

"I welcome scientists and academics to join us in making social change for the good of our country, but there will be no room on this waka for bias and stereotypes."