Police officers were wrong to ignore instructions and chase five young people in a stolen car down an Auckland motorway, the police watchdog says.

Photo: 123RF

During the pursuit, in 2017, the Toyota was driven the wrong way down the Southern Motorway for about 9km.

In its report, the Independent Police Conduct Authority (IPCA) found the officers were not authorised to initiate a pursuit and ignored directions to abandon it.

Initially, the police northern communications centre shift commander, who is responsible for controlling any pursuits, authorised the use of road spikes to stop the car, even though the officers at that point had not signalled for it to stop.

The car was being driven erratically after the first failed spiking attempt and shortly after one of its rear tyres was successfully spiked.

The shift commander told the officers not to pursue the car.

Despite this, at least two police cars followed close behind it and a chase began when one of those cars turned on its flashing lights and siren.

At no stage did the police follow the correct procedure for starting a pursuit, the IPCA said.

The driver of the car then drove up the Takanini off-ramp and continued to drive on the wrong side of the Southern Motorway into heavy oncoming traffic.

After the car left the motorway at East Tamaki Road, the shift commander authorised the use of a 'moving block'.

This tactic for stopping a fleeing driver's car was not included in police policy and officers were not trained to use it.

Officers attempted and failed in this manoeuvre, then one officer nudged the car with his patrol car to prevent the car re-entering the motorway. This also failed.

Soon after, the shift commander directed that the pursuit be abandoned. In contravention of police policy, officers continued to pursue the car at speed.

The car then came to a stop and one officer's car hit the driver as he attempted to flee on foot.

IPCA chair Judge Colin Doherty said police should not have conducted a pursuit.

"The police helicopter was tracking the Toyota and could have continued to do so to assist in apprehending the occupants," he said.

"Engaging in a vehicle pursuit so late on a Friday morning, when there was substantial traffic on the roads, placed members of the public, police and the young people in the stolen car at unnecessary and ongoing risk.

"Police failed to formulate a suitable plan; the number of cars involved in the incident and the tactics employed were inappropriate and only served to increase the risk to everyone."

The IPCA found that the shift commander failed in his command and control responsibilities.

This created an atmosphere of confusion and was a significant contributing factor in the poor tactical decisions made by other officers involved in the incident.

A police dog handler used his dog to help with the arrest of two of the young people. One suffered injuries resulting in his hospitalisation, and the IPCA found that the use of the dog was an excessive use of force.

In a statement, the police said there were elements of the pursuit that could have been better managed.

"This was a fast-moving and complex incident and our officers had to make spilt-second decisions in a situation involving very dangerous offenders," Acting Superintendent Dave Glossop said.

"Ultimately in pursuits it is the offenders who choose not to stop for police and in doing so put themselves, police staff and members of the community at risk. In this case, the offenders were driving on the wrong side of the motorway.

"It is through sheer-luck that innocent members of our community were not seriously injured."

Police said they had communicated the lessons learnt from the incident to the staff involved.