Zara Mitchell, 18, died when the car she was in crashed into a house near Rangiora after fleeing police last September.
Police officers stopped a vehicle with three passengers in Christchurch in the early hours of 17 September last year and discovered the driver, then 18-year-old learner driver Adam Michael Rapson, was in breach of his licence conditions and the vehicle, a Ford Falcon, was not roadworthy.
Police issued Rapson with an infringement notice and issued the vehicle with a pink sticker, ordering it off the road and instructing him to drive it directly to his father's address.
The officers intended to escort Rapson home, which is common practice, but a decision was made to attend a burglary that was underway at a liquor store in Lincoln.
The IPCA found the decision to allow Rapson to drive to a nearby address was lawful and reasonable in the circumstances.
However, Rapson continued to drive around Christchurch and then to the outskirts of Rangiora where the group joined a large group of car enthusiasts to do burnouts, which led members of the public to call police to report disorderly behaviour.
Police arrived in the area to find most of the vehicles had left, but saw the Falcon which they learnt had earlier been pink stickered. After driving past it, Rapson did a U-turn and accelerated at high speed along Oxford Road towards Rangiora.
The officers responded by activating their lights and signalling the driver to stop. When it became clear that the driver was fleeing, they abandoned the pursuit.
Rapson later told told police after seeing the patrol car, he and his friends got into the car and they began screaming at him to go so he "gassed it out of there" towards Rangiora.
He said he saw blue and red flashing lights behind him and when he asked his friends what he should do, they slapped the back of his seat and screamed at him to go so he, "just floored it ... I took off out of there like my hair was on fire".
The Falcon then hit a tree and crashed into the side of a house on McIvor Place, killing 18-year-old Mitchell, a back-seat passenger.
Rapson was sentenced to three-and a-half-years' jail in the High Court at Christchurch in April, on a charge of manslaughter, two of dangerous driving causing injury, one of fleeing the police, one of driving unaccompanied on a learner licence, and one of driving a vehicle ordered off the road.
The court heard how he had consumed cannabis throughout the day, and was travelling at about 140kmh when he lost control of the vehicle.
The IPCA found the officers should have notified the Emergency Communications Centre (ECC) of their intention to signal the Falcon to stop before activating their lights and siren. It also found that, after abandoning the pursuit, one of the officers misled the ECC by advising they had come to a stop on Acacia Avenue, which they had not.
Both omissions were in breach of the Police Fleeing Driver Policy.
The policy states that in deciding whether to stop a driver: "Consideration should always be given to delaying the signal to stop while coordinating tactical options or waiting for the wider environment to become safer to reduce risk."
It also states that if there are indications a driver is likely to flee, the ECC must be advised of: "The reason for wanting to stop the driver; the intention to signal the driver to stop; and whether a pursuit is going to be initiated if the driver fails to stop."
A pursuit must be abandoned if the officer determines that the risks outweigh the necessity to continue the pursuit.
Canterbury District Commander Superintendent Tony Hill said while some elements of its procedure were not followed in this case, the overall decision-making had been sound, and it was pleased the IPCA had found the officers did not cause the crash.
Hill said police were required to make quick decisions in high-pressure, dynamic situations every day and he asked those who were signalled to stop by police, to do so.
"It's not worth risking the lives of yourselves or others, and you are putting everyone in harm's way when you choose to flee."