Justice Andrews noted a phychiatrist's report that indicated Pakau had been depressed at the time, due to difficulties in his relationship, the sickness of one of his children and the passing of his stepfather whom he was very close to.
The father-of-five was well supported in court. Several members of the packed public gallery broke into tears when his jail sentence was announced.
Justice Andrews denied a discount for previous good character, as she said it had enabled his offending.
"It must have been clear to you that what you did was completely against the oath you took when you became a police officer," she said.
"The harm the community has suffered should not be underestimated."
Justice Andrews referred to a victim impact statement by Detective Inspector Bruce Scott of Waitemata police, which said Pakau's actions had placed his colleagues in potential danger, showed them a "lack of respect" and undermined the authority of the police.
Four of the ten people originally named as Pakau's co-offenders were sentenced to shorter jail terms at the High Court today.
Defence lawyer Ron Mansfield disagreed, saying previous reports of Pakau's "exceptional" policing showed he was not inherently bad - he had allowed himself to be manipulated.
"He wasn't driven by an evil motive or financial desire... he saw it initially as a means to an end but became too involved," he said.
Crown prosecutor Ben Finn said Pakau had tried to please his colleagues and bosses within the police at the start, but his motivations changed as he began trying to "ingratiate" himself with his co-offenders.
"This appears to have lead him to be allowed to be manipulated for criminal ends," he said.
"His offending may have begun as a lapse of judgement early on but as it escalated in seriousness and frequency it must have become clear to Mr Pakau how wrong his actions were."
Pakau did not appear to be motivated financially, though financial gain had certainly played a part in the scheme, he said.
Mr Finn asked that Pakau not receive a reduced sentence for having good character references, as he said it was important the court deterred others from abusing positions of trust and authority.
Afterwards, Detective Inspector Bruce Scott said Pakau's actions had had a big impact on the day-to-day business of his colleagues and on the community.
He described Pakau as a "bad apple" and said he was definitely not the "exemplary police officer" his defence lawyer described him as once being.
The long and thorough investigation into Pakau begun after fellow police officers became aware of his actions, he said.
"I'm very pleased it has finally come to an end," Mr Scott said.
