A fake couple, a storage shed, and planted stolen goods were part of the elaborate police undercover operation to take down the Nelson Red Devils Motorcycle Club.
Police infiltrated the gang over several months, using an undercover officer known as "Michael Wilson".
Wilson told the Red Devils that he and his partner were moving to Nelson from the North Island to start afresh.
Details of how Wilson first gained the confidence of the gang's members are suppressed. But court documents show that early on in his attempts to infiltrate the Red Devils, he rented a storage lock-up in a complex in Motueka, which police wrongly believed was linked to the gang.
In his decision yesterday, Justice Simon France said that as part of the police's strategy to strengthen Wilson's credibility, they planted stolen equipment in his lock-up. They also planted equipment consistent with involvement in cannabis offending.
Police wanted intelligence on the Red Devils because they believed the gang was a puppet gang of the Hells Angels. As well as undercover agents, police had search warrants to intercept phone calls and text messages. They also installed listening devices, and this resulted in a huge amount of paperwork that was disclosed through the court process.
Police became anxious for the undercover officer and feared that their covert operation, code-named Operation Explorer, would fall over after Red Devils members became suspicious that he was a policeman.
Patched Red Devils member Lucky Tulouna, who has since died, confronted the officer, telling him the others were worried that he was a cop. Police decided that it was necessary to strengthen the officer's criminal credibility, and decided to stage a fake arrest of him. To ensure that the arrest was public, police summoned the owner of the storage facility and showed him a fake arrest warrant a police officer had signed, purporting to be a deputy registrar of the court.
Justice France said the court's processes had been abused in a "significant way", and he was suprised by the officers' lack of insight about the inappropriateness of making up a fake search warrant and using it on a member of the public.
It reflected the police's lack of a hard look at the reality of what they were doing, and the "too ready assumption that the police perspective was correct", he said.
After searching the lock-up, police met with their superiors to seek advice on what to do next. They decided to continue with the ruse and arrest Wilson on false charges.
Wilson was arrested by a police officer near the Red Devils' headquarters on the Saturday after his storage unit was searched. The officer knew that Wilson was an undercover officer.
Wilson appeared in the Nelson District Court on charges of possessing equipment to cultivate cannabis. However, the police's plan for him to plead guilty early was ruined when a Red Devils member learned of Wilson's arrest and suggested a defence lawyer for him to use.
The lawyer, believing Wilson to be a real defendant, advised him to plead not guilty, drawing out the court proceedings.
Wilson failed to appear in court twice to boost his credibility. It was also revealed in court that Red Devils members chastised him for doing so.
Police withdrew the charges when Operation Explorer was terminated in March 2011.
Justice France said police believed they had authority to carry out the false prosecution because of a visit to the now deceased Chief District Court Judge, Russell Johnson. In keeping with police policy on the staged arrested of an undercover officer, police prepared a report for Judge Johnson outlining what they were planning, and the charges.
The report did not include details of the officer, his name, the charges he would face or the court he would appear in. Those details were in a separate, sealed envelope, which would only be provided to the judge if he asked to see it.
It was revealed in court that Judge Johnson only asked the vague details of the case, and was told it was gang-related.
The meeting ended, and the envelope with the details outlining the charges remained sealed.
Justice France said Judge Johnson would not have had any experience of a similar false prosecution as an investigative tool, and there was nothing in the letter to alert him to the fact that the arrest was made up, and the "realities of what was involved".
"I do not accept that the chief judge and the police were on the same page."
He said he accepted that the police were acting in good faith, but they did not get legal advice, and had "too ready an assumption that the police perspective was correct".
"However one looks at it, a fraud is being committed on the courts."
He said he expected that as a consequence of this judgment, police would change their practices.
He doubted that a false charge would be sworn against an undercover officer again.
The names of those who had charges dropped against them are: Taylor Ivan Antonievic, Thomas Joseph Bashford, Natalie Jean Busch, Colin Chinnock, Jordan John Daly, Jason Peter George Friend, Jason Paul Griffiths, Grant Roy Hayward, Terry Jones, Hayley Joanne Kirkwood, Mark James Lee, Russell Phillip Lloyd, Joseph Mark Pahl, Gregory Jon Page, Roger Paul Patrick, Glyn Patrick Rutledge, Craig Peter Smith, Damian John Stacey, Robert John Stewart, Glen Ross Thompson, Trevor John Momo Wilson.
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