Named as head of the region's organised crime unit, he led police teams on the annual cannabis recovery operations.
But then the thin blue line blurred. Blowers abused his trusted position.
While he was tasked with stamping out drug dealers, he became one.
During the first day of the trial on Tuesday in the High Court in Whangarei, the jury of seven women and five men heard how Blowers had stolen seized methamphetamine from a secure police lock-up and then used a woman to sell the Class A drug for "thousands of dollars".
Crown solicitor Philip Hamlin said there was "one reason only" why Blowers had embarked on his criminal career, and that was money.
He had teamed up with the woman, who can't be named for legal reasons.
"He had the source, she had the contacts," Mr Hamlin said. "He effectively created a drug network from his position of trust. He was the source and had access to the drugs."
The Crown outlined its case and said Blowers stole methamphetamine from the Whangarei police station drugs storeroom on or about October 19, 2011. He then tried to cover up the theft by replacing the white-powdered drug with table salt. The 58g of methamphetamine had been seized by police during a raid on a Whangarei motel.
The court was told Blowers had limited access to the drugs store in the main body of the station, where most of the seized methamphetamine was "posted" in an envelope through a locked door. However, he had unlimited and unsupervised access to the bulk drugs store, where bigger items including large amounts of cannabis were kept on the top floor of the Whangarei police station.
However, his handling and storage of drugs, particularly methamphetamine in two drugs stores at Whangarei police station, was subject to an employment review with his superiors.
"He wasn't following the rules," Mr Hamlin said.
Blowers had been putting methamphetamine in the bulk store and had been told by his superiors to stop.
Six months later he was moved to the child-protection unit and there were no suspicions about the missing drugs.
But Blowers' network began to unravel when the alarm was raised by a fellow detective who had worked on Blowers' Organised Crime Unit.
Media have previously reported the detective became suspicious of Blowers' behaviour and tailed his visits to the home of a Whangarei woman before handing a dossier - which included covert photos - to senior CIB management.
But instead of investigating Blowers' movements, police management removed the whistleblower from the organised crime unit and placed him under strict supervision.
The officer was subject to an internal code of conduct inquiry and it was thought he may have breached protocols around the use of the National Intelligence Application computer system, to be used only for official police business.
The officer was cleared and then the attention turned to Blowers.
A police team from outside Northland was brought in to investigate and interviewed senior officers in Northland who had worked on the frontline with Blowers for years.
Extensive audits of how drugs were handled and stored at the Whangarei police station were carried out. Blowers resigned from his job two weeks before his arrest.
Of the 40 witnesses expected to give evidence during the trial, at least half were police and they included some top-tier Northland officers.
Up until trial, Blowers vehemently denied the charges.
But on day three there was a U-turn, with Blowers changing his plea to guilty of stealing and supplying methamphetamine.
As two charges were read, Blowers stood, dressed in a black suit and tie and flanked by a security guard, and uttered the words "guilty".
As he watched his wife, parents and supporters leave the courtroom, it was clear Blowers was upset.
Outside court, lawyer Arthur Fairley said new evidence given to the defence after the first day of evidence had been "irrefutable".
It was new evidence regarding the handling and processing of methamphetamine seized in a drug raid at the motel.
"The candidates who could have done it were reduced to Mr Blowers," Mr Fairley said.
"He's dreadfully upset. He has a family and he has been a police officer in Northland a long time before his fall from grace.
"He understands he has let himself down and the community he served.
"He's ashamed he has let down people he has worked with side by side on the front line."
Blowers has been released on bail until he is sentenced on December 3.
-additional reporting New Zealand Herald
