A mentally distressed woman suffered a torn knee ligament while a police officer worked to restrain her in the back of a patrol car.
But the Independent Police Conduct Authority (IPCA) has found that while the woman's injury was regrettable, the officers' actions were "reasonable and appropriate".
According to its report released Thursday, two officers were called to the rural Taranaki town of Matau in the early morning of 18 Apri, 2021.
Residents had alerted police about the woman, who was dressed only in her underwear and appeared to be having a mental health crisis.
She had entered a house around 3am, waking the occupants and exposing herself to them while making unusual comments and statements.
Police arrived and decided to take her to Taranaki Base Hospital for a mental health assessment. They believed she was at risk of hypothermia or being hit by a car.
The woman, who has bipolar disorder and had been assessed as being aggressive with a history of violence, resisted, so the officers handcuffed her before placing her in the patrol car.
When she refused to pull her legs inside the car, an officer pushed her legs inside so they could close the door.
On the drive to the hospital, the woman tried to kick the driver from the back seat. The officer beside her restrained her by wrapping his arm around her legs.
The woman then felt "an excruciating pain", heard a "pop" and felt her left knee collapse under her, she told the IPCA.
She was admitted to the mental health unit where she complained of ongoing knee pain.
The woman was later diagnosed with a complete anterior cruciate ligament or ACL tear.
She complained to the authority, claiming the officers caused her injury through their use of force and that they had used an inappropriate method of restraint, that being when the officer held her legs in the patrol car.
The woman also alleged the officers deliberately took a longer route to the hospital, adding more than 30 minutes to the trip.
But the authority found police were justified in detaining the woman under the Mental Health Act, and the officers' use of force and method of restraint was reasonable and appropriate.
The IPCA report said the officers took a longer route because they mistakenly believed a road led to a dead end.
One of the officers heard the popping or clicking sound from the woman's knee, but the cause of her injury could not be conclusively identified.
"If the officers' actions did cause the injury, our view is it was an unintended and regrettable consequence of their attempt to get her in the patrol car," the report said.
"The officers were motivated by the woman's need for mental health support and acted lawfully to overcome her resistance," said authority chair Judge Colin Doherty.
But it was regrettable that their actions may have caused or contributed to her knee injury, he said.
Police have acknowledged the findings and said officers are trusted to make the best decisions possible at the time to ensure people's safety and well-being, and routinely look at what lessons can be learned.
"Police officers go to work every day to keep people safe, and part of this work involves incidents where people are in mental distress," Central District Commander Superintendent Scott Fraser said.
* This story originally appeared in the New Zealand Herald.