A former police officer says bullying in the police is having an impact on the public as well as the organisation itself.
RNZ has talked to more than 25 people who have been victims of bullying or witnessed it in the police, and they say it's a widespread issue led by senior staff members.
A former detective said the bullying in the police stemmed from an abuse of power.
People who were promoted to senior supervisor roles were sometimes using their newfound power to "make life hell" for those beneath them, RNZ was told.
The people RNZ talked to said it came right from the top, including members of the police's executive team.
The bullying has had a serious impact on the staff themselves, but as a former detective said, it is also impacting on victims of crime.
"It's been ridiculous to the point of, we've had statements taken of witnesses, and people have had to go and adjust those statements because the person who's read it doesn't like the way it's worded," they said.
"So you have to go back to those witnesses and redo the statement.
"It's not that you're doing your job wrong, it's that one person doesn't like how you've done your job, and that's bullying."
The former detective said people have had to rehash at times traumatic incidents in order to satisfy a bullying boss.
A former sergeant, who also asked not to be identified, said a key issue was the way the police selected its managers, and that they were not trained to be leaders.
"Management is very different to leadership," he said.
"They train management, and you can learn that because desktop management, you could learn that in umpteen dozen ways, but leadership is something that you need to forge at a personal level, at the coal face.
"It has to be learned on the job. The police do that particularly poorly."
Several people RNZ talked to said to avoid bullying, you needed to be part of the "mates club".
If you were outside that club, you were more likely to become a target of workplace bullying, and your chances of career progression would take a hit.
The former sergeant said he only realised in hindsight that he was a victim of bullying, and that he did not feel valued by his bosses.
"The question you should be asking a police officer is, do you feel valued?," he said.
"Yes, most officers will say, 'I do feel valued', but they feel valued by the public, not from their superiors. That's where it should come from, and it's not."
The police commissioner, Mike Bush, declined an interview with RNZ about the bullying claims.
But in a statement, deputy chief executive Kaye Ryan said the police were reviewing their complaints procedures.
The police minister, Stuart Nash, declined repeated requests for an interview, saying bullying was an operational matter best answered by the police commissioner.
The National Party's police spokesperson, Brett Hudson, said Mr Nash should front on the issue himself.
"I think he should be a little clearer in his expectations, a little clearer about what he is going to demand in way of response from police," Mr Hudson said.
"I don't think he could, or should, be dismissing this as an operational matter.
"I think in general the public would expect the government and the minister to have a little bit more of an interest in matters such as these."
Mr Hudson said he took heart from the fact that the bullying culture was not universal in police.
But he, and others, said the police did need to show the public and their own staff that they were taking complaints of bullying seriously.