The number of complaints to the Independent Police Conduct Authority alleging police misconduct is steadily rising.
Already complaints have surpassed last year's total of close to 2200 and the authority is expecting the number to reach 2500 by the end of June.
IPCA chair Judge Sir David Carruthers Photo: RNZ / Alexander Robertson
IPCA chair Judge Sir David Carruthers attributed the rise to the profile of the authority and the ease with which people can lay a complaint online.
Despite the high volume the authority was managing to work within its budget and deal with each complaint fairly.
"We are still at pains to ... make it clear if we think someone's not behaved correctly," said Sir David.
"But if at the same time, we can look at the theme and the structure and we can prevent something in the future, then clearly we ought to."
The authority has in the past two years gone from publishing a select number of reports it considered of public interest to publishing all reports.
Sir David said while he feared they were "over-reporting" on alleged police misconduct last year, he believed they now had the balance "about right".
"We don't have a real interest in just being critical and blaming for anything that goes wrong in a very difficult job," he said.
"We have to have the courage to speak out if we think something's wrong. But we also need to think about prevention much more than just blaming - so we're trying to make that move as well."
Ella Eketone, 15, had two teeth knocked out and sustained facial injuries from police officers trying to break up a party. Her complaint was upheld by the IPCA last year.
The report, which criticised police handling of eight out-of-control parties over a five-year period, found that in Ms Eketone's case, the police used unjustified and excessive force when shutting the party down in 2013.
Ms Eketone, now 17, said she tried not to dwell on what happened. She said the ordeal had opened her eyes to the very real issue of police brutality and she was still pursuing compensation through the courts.
Increase at lower level, say police
Police have downplayed the rising number of complaints.
Deputy commissioner of resource management Glenn Dunbier said most of the increase related to lower-level, or category five, allegations of misconduct.
"There has been a significant decrease in complaints in the more serious matters, with category one complaints down 40 per cent odd, the others around 30 [percent]."
The complaints came at a time when police were dealing with more incidents than ever before, Mr Dunbier said. Calls to the service had increased 21 per cent in the past year.
Police in Canterbury had the highest number of complaints against staff in the year ending June 2013, with numbers dropping only slightly last year.
Detective inspector Tony Hill said those complaints, which largely related to attitude and interaction, prompted a professional shake-up among staff last August.
"The senior sergeants decided that they were concerned about the level of complaints and wanted to do something about it.
"So as a district, we started an initiative around professionalism. And from there, we've had a dramatic decrease in the number of category four and category five complaints."
