A 28-weeks pregnant woman was injured and hospitalised last year when a police officer "did not consider the basic principles of police policy" and threw road spikes into the path of the wrong car, the Independent Police Conduct Authority says.
The Independent Police Conduct Authority has found road spikes were wrongly deployed in a bid to stop a fleeing driver near Puhoi, north of Auckland, last February.
About 2pm on 28 February, police in Manurewa started pursuing a stolen Mazda Demio which turned onto State Highway 1 and headed north.
Police said the driver - eventually found to be a 14-year-old - had failed to stop for them and was seen driving erratically and at excessive speeds, running red lights before heading north on SH1.
The driving was "putting other motorists at risk", police said. Officers and the Eagle helicopter engaged in the pursuit.
Meanwhile, an officer in an unmarked car was listening to reports of the incident on police radio. He was concerned the fleeing driver would reach a dangerous section of road between Puhoi and Warkworth, where he was located.
The officer was given clearance to lay spikes at the north end of the Johnstone Hill tunnel, but mistimed their placement.
Instead of the spikes being thrown in front of the Mazda, they were laid in the path of the pregnant woman's Suzuki Swift.
As she braked hard to avoid the spikes, the fleeing car rear-ended hers, forcing her over the spikes, the IPCA said.
She hadn't been aware of the stolen car behind her, and recalled it hitting hers with a "massive force".
The stolen vehicle drove around hers, over the spikes and continued for a short distance then crashed, and the two occupants were arrested by pursuing officers.
The stolen Mazda's 14-year-old driver was charged with multiple offences and dealt with through the Youth Justice system. The passenger, aged 11, was referred to Youth Aid.
The pregnant victim was taken to the North Shore Hospital and had injuries that "affected the rest of her pregnancy", as well as trauma and stress, according to the IPCA report.
She was released from hospital the day after the incident and had since given birth to a healthy baby.
However, she told the IPCA the incident had a "significant and ongoing impact on herself and her family".
Police conducted an employment investigation in relation to the officer's actions and later wrote to her to apologise.
The location chosen by the officer to lay spikes "did not comply with police policy because it did not provide sufficient cover so as to ensure his safety and that of other road users," the IPCA said.
"Further, the officer was not clearly identifiable to road users, as he was wearing neither stab resistant body armour nor a high visibility vest, and had not activated the emergency lights of his police car."
The report later said: "In his haste to deploy road spikes to stop the fleeing driver, the officer did not consider the basic principles of Police policy and prioritise the safety of other road users and himself. As a result, an innocent member of the public suffered injury and trauma."
The IPCA found that police were justified in pursuing the car and it was satisfied police complied with policy during the pursuit.
It also found road spikes were appropriate in principle but should not have been used because the officer "did not undertake an adequate risk assessment and did not comply with police policy. Specifically, [he] did not prioritise the safety of himself or [the Swift driver] and other members of the public over his perceived need to stop the fleeing driver".
Police also ensured the woman had timely and appropriate medical response.
The were also justified in an armed arrest given they had earlier been warned the driver could be armed.
Police said they accepted the IPCA report.
Waitemata District Commander Superintendent Naila Hassan said officer's actions were made in good faith and they acted with the best of intentions.
"This was a fast-moving and dangerous situation where we had a fleeing driver who was posing serious risk to the safety of other motorists and needed to be stopped.
"Our officers come to work every day to protect the community and keep them safe.
"However, I do acknowledge the officer made errors on this day in the deployment of road spikes and I accept that their actions did not comply with Police policy.
"Police have reviewed this matter to evaluate what learnings can be taken from this incident."
The officer subsequently received further training around the deployment of road spikes.
"We have also apologised to the victim in this matter and expressed regret over what has taken place, while also offering her victim support."