New details have been revealed about the extent of regular fight clubs largely organised by gangs - and staff involvement - at the Serco-run Mt Eden Prison.
The Corrections Department has today released the long-anticipated report which the private prison operator had tried to block.
Highlights of the report came to light in a High Court judgment in August, which said fight clubs happened at least once weekly and often took place in full view of CCTV cameras, and inmates were also likely served up animal-contaminated food.
The Chief Inspector's report says five confirmed fight clubs, and two other probable ones, happened from mid June to mid July, along with 12 incidents of sparring.
It said the fighting ranged from 15 to 50 minutes, involving multiple rounds between inmates, and was most prevalent in Delta Unit cells and the Alpha Unit yards.
"The lack of an effective control environment at residential unit level including in particular insufficient 'staff on the floor' provided prisoners with opportunities to participate in organised fighting and other illicit activities," the report said.
Fighting was probably organised by senior members of gangs, and some of the prisoners said that if they refused to engage they were "threatened", "pack attacked" or assaulted by senior members of the Killer Beez, Head Hunters or Black Power.
On one occasion, a staff member was identified in CCTV footage as participating in sparring but the report found there was insufficient evidence to conclude that staff were directly involved.
"While possible, it was unlikely staff were involved in organising and betting on these fights."
The report also said it was "likely staff were the primary source of contraband and that it was freely available".
It said some inmates were denied their basic right to a phone call - some for as long as five weeks.
The poor level of kitchen sanitation was highlighted, with photos showing how food was likely to have been contaminated by birds and other animals because of the way it was left out.
In response to today's report, the Corrections Department chief executive Ray Smith said Serco had been held to account for its failings.
He said since the the department stepped in and took control of Mt Eden Prison, it had strengthened searches for contraband, ensured staffing levels are adequate and improved the kitchen hygiene standards.
Mr Smith said staff had had further training and two new security roles had been created.
He said 13 of the Chief Inspector's recommendations had been completed and another eight were underway.
Mr Smith also pointed out that no evidence of fight club activity at eight other prisons in New Zealand had been found.
Serco's Asia Pacific chief executive Mark Irwin said important lessons had been learned and the company had paid the Crown an $8 million fine and other costs as it ended its contract.
He said after Serco began running Mt Eden Prison in 2011 incidents of violence and incidents of self-harm fell to an all-time low and the prison ranked top in the country for reducing re-offending.
Corrections Minister Judith Collins said she would legally require the department to release inspectorial prison reports in the wake of the inquiry.
Ms Collins said better reporting procedures were needed.
"I expect far better transparency around inspectors' reports, which have previously always been not disclosed. So, both to myself as the Minister, but also available to the public."
Ms Collins said she would present legislation containing the new reporting procedures to Cabinet.