Criminal justice reform advocates hope new research into systemic racism within the police can reverse decades of bias against Māori and Pasifika communities.
In March, the force launched a long-term research project with the University of Waikato's Te Puna Haumaru NZ Institute for Security and Crime Science, "examining where bias may exist within police policies, processes, and practices".
"We have a great organisation, and people out there are making a huge difference - people join police to make a difference, they come to work to do a great job," Police Commissioner Andrew Coster told Newshub Nation on Saturday morning.
While acknowledging they don't always get it right, Coster said officers on the whole are "not racist".
"From time to time in an organisation of 10,000 officers, people will let us down. We deal with that really clearly."
But he said the criminal justice system as a whole is "getting unequal outcomes for different groups" - which he hopes the research will fix.
"We have for the last 20 years enjoyed increasingly strong relationships with iwi and Māori. Our people are exceptional... we are on a journey, and our people are very open to these conversations and where we need to go."
Sir Kim Workman will chair a group that will provide expert, independent, academic, cultural and community advice to the research programme. He said there have been reports going back 60 years pointing out racism in the police force and justice system that have been largely ignored - but this new probe is "exciting".
"It's the first time I think any Government agency has taken this extra step of saying, 'We seem to have unfairness, inequity in our system. Let's look at where that happens, why it happens, how it happens and what we can do to reduce it.'
"So we're starting to really dig deep into the behaviour and that culture, and the practises and policies that are there, and really looking for evidence of bias wherever it might be. So I think it is different."
Academic and lawyer Litia Tuiburelevu, appearing with Sir Kim, said she remains sceptical.
"Racism is embedded into the structure and the institution of police since the police came to Aotearoa - that started as an armed force that suppressed Māori resistance. We've seen that repeat throughout history...
"I hope that narrative of racism and settler colonial violence and white supremacy is centred in this and we are able to reckon with that - as uncomfortable as it may be."
She said even if individual officers aren't racist, young Pasifika or Māori don't know that.
"I know the commissioner may talk about having, there may be good cops, they may be nice and well-intentioned, but that's not how a young Pasifika or Māori man relates to police - they see them as an agent of the state. There is a complete power imbalance - they are able to use force against them, and often they do."
Coster hopes the research will help police and critics stop talking "past each other".
"What we know is Māori are grappling with a range of disadvantage, more so than other parts of our population. We see that in terms of drug and alcohol issues, mental health issues and family harm. So those make up the mix police deal with and the incidents we respond to.
"We need to be able to separate what's upstream of police in terms of those kinds of issues, and then what are the things police might need to do differently in order to make sure that we're being fair for all people. The research will help us understand that."