The Police Commissioner has hit back at what he calls a "racist slur" made by Maori Party co-leader Pita Sharples.
Dr Sharples launched his party's justice policy earlier in October, saying the system is unfair, biased and prejudiced.
He said the sector, including police, discriminates against Maori.
But Police Commissioner Peter Marshall says he does not agree there is a racial bias in police dealings with Maori.
Mr Marshall says he admires and respects Dr Sharples and shares the politician's concerns about over-representation of Maori as victims and offenders in the criminal justice system.
But the country's most senior officer says he will not stand by and not challenge a slur that racism is an intrinsic part of New Zealand police culture.
However, Mr Marshall says in an organisation of 12,000 people there will be staff who let him down, but racist attitudes will not be tolerated.
The top police officer acknowledges that politicians make big statements on law and order - especially in the run-up to a general election.