A police officer unjustifiably punched a small 13-year-old boy multiple times in the ribs during an arrest, the Independent Police Conduct Authority has found.

Photo: RNZ / Patrice Allen

Police also did not seek immediate medical help for the boy despite him having a cut and bruised head sustained during the arrest.

Police say they support the officer's actions, "given the complex and fast-moving situation our officers were faced with".

Late at night in May 2018, the boy (Mr X) was in a stolen car with six others in a police pursuit originating in Auckland's south. The car was eventually spiked and stopped near the Johnstone Hill Tunnels on the city's northern outskirts. Five police cars were there.

The boy was pulled out of the car by a police officer (Officer A), and hit his head on the motorway safety barrier. The officer said he did not know who was inside the passenger seat, and he used the amount of force required to get an adult out. Because the child was lighter than he expected, the boy moved further than he thought and hit his head. The officer denied this was intentional, however the boy said he tried to do it twice.

The boy sustained a cut and bruised forehead, a cut above his lip, a bruised right eye and a grazed to his left hand, elbow and right knee. He was not seen by a doctor until 12 hours later.

With the child restrained on the ground, another officer arrived on foot to assist the first. The child did not offer his hands for arrest, so the officer punched him in the ribs two or three times times to handcuff him.

The IPCA found the punches were not justified.

"By this time, Officer A could see that Mr X was young, of small stature, and someone he could easily overpower. Constable C had also arrived to assist. The Authority is of the view that Officer A should have given Mr X more time to comply and made further attempts to encourage this through clear communication," the report found.

The IPCA found the use of force to remove him from the car was justified, and although the head impact on the motorway barrier was unintentional, the officer could have taken more care to prevent this.

The boy was arrested for breaching bail relating to an earlier charge, in which he had a 24-hour curfew.

Later the boy was crying, had a lump on his head, and said he had head pain rated seven out of 10.

However, he declined medical help, so police did not immediately call a doctor for him. They eventually did at 9am, and the doctor arrived just before midday.

"The Authority finds that due to Mr X's age and the nature of his injury police should have arranged for him to receive medical attention as soon as possible, despite him saying he did not want this. Police neglected their duty of care in failing to do so," the report found.

"It is also concerning that there was a delay of almost three hours in the doctor arriving, with no apparent follow up calls from police regarding this, and that Mr X was allowed to go to sleep before being medically assessed, when it was possible he had a concussion."

The officers were justified in arresting the boy, and detaining him until they were able to released him to Oranga Tamariki.

In a statement from police, Counties Manukau District Commander Superintendent Jill Rogers said: "The IPCA found [the use of force] was not justified however I support his actions given the complex and fast-moving situation our officers were faced with.

"The teenager was offered medical treatment on a number of occasions by our staff but we accept that given the offender's age, they could have considered arranging for him to be seen by a health professional."

She said police undertook their own investigation that "found the arrest and force used was justified".

However in the IPCA report it said the police reached similar conclusions to its report on Officer A's use of force, and that he completed extra training on decision-making and communication.

When asked about the difference between these two interpretations, and whether the officer did or did not receive extra decision making training, police responded: "Our investigation found that the arrest and use of force was justified.

"Police are not obligated to comment on internal matters and we must ensure the privacy of our officers. We can say that our staff receive regular training and where there is an IPCA matter we will always look for learnings."