KEY POINTS:
A review of Operation Austin - the investigation into Louise Nicholas' allegations of pack-rape and corruption by police - has thrown out complaints by former assistant commissioner Clint Rickards and his supporter former All Black Steve McDowell.
Operation Austin began in 2004 after allegations by Louise Nicholas were made public.
The investigation was headed up by Detective Superintendent Nick Perry who is now New Zealand Police's liaison officer at the High Commission in London.
Rickards has been scathing about the police team set up after Nicholas' allegations surfaced, and had filed 15 complaints with the Police Complaints Authority.
He has described Operation Austin as "a shambles" and "one I would have been ashamed to lead".
Yesterday he told Radio Waatea host Willy Jackson that he had issues with some members in the police force.
"I've got no gripe against police. I have got some issues with certain areas in the police. I'm not about to bag police after 28 years," Mr Rickards said.
But the review of Operation Austin concludes that the investigation, given the number of complaints against police, was not drawn out.
It gives a unique insight into a police investigation described by Detective Superintendent Perry as going into "unchartered waters".
The report said: "The inquiry was almost overwhelmed by new issues and allegations virtually every week, many remarkably similar to the Louise Nicholas case."
It continues: "staff worked weekends for a month just to keep up, but as more cases came in, all of them inter-related, the volume grew and Detective Superintendent Perry could not see how to investigate and process it any faster."
The report recognises difficulties in the case, including the time that had elapsed and a lack of forensic evidence. It also said that it was "particularly challenging" given that Rickards, Shipton and Schollum were experienced in police investigation methods.
The report dismisses Rickards' public criticism of Operation Austin. "It appeared to the authority that whilst the assistant commissioner has accused others of bias, he has on occasions engaged in precisely the same behaviour," the report said.
Mr Rickards and former police colleagues Bob Schollum and Brad Shipton were found not guilty in March of kidnapping and indecently assaulting Louise Nicholas in Rotorua more than 20 years ago.
Ms Nicholas has described Operation Austin as being responsible for restoring her faith in the police force.
She has previously told the Herald that she no longer felt "shivers of fear" when she saw a blue uniform.
The review into Operation Austin was carried out by former commissioner Richard Macdonald and former acting deputy commissioner and acting assistant Commissioner Roger Carson.