The son of a pregnant woman killed in a police pursuit has pleaded with drivers not to flee police and risk their lives - or those of others.
But the mother of a teen killed in a crash is calling on police to pull back on pursuing fleeing drivers, particularly youngsters behind the wheel.
The two spoke out this week as part of The Chase, a four day Herald series taking an in-depth look at pursuits ahead of the release this Friday of a major review on the polarising police practice.
Police have engaged in more than 30,000 pursuits in the last ten years, during which time 79 people have been killed in crashes. Others have been killed in pursuit-related incidents including police shootings - and hundreds, including those in the fleeing cars and the patrol cars chasing them, have been injured.
The Chase looks at why pursuits happen, how police respond and who is affected.
Jacob Percy's pregnant mother, Renee, was killed in December when the car she was a passenger in crashed into a power pole during a pursuit. Driver Dennis Tunnicliffe was also killed.
"It's not worth it," Jacob Percy said.
"There's no two ways about it. People can stop, so they should."
The teen was critical of the frequency of pursuits.
"I believe they need to make quite a few substantial changes," he said.
But he acknowledged it also depended on the circumstances at the time. Pulling back was the right option if police knew who the driver was, he said.
He was mostly concerned about the "horrifying" number of associated deaths, and that innocent people, including his 35-year-old mother, had died.
The teenager said his mother had been in trouble before but "wouldn't ever run away from the police".
Elizabeth Harrison's daughter, Eden Nathan, was just 16 when she died in a police pursuit three years ago.
Eden was the passenger in a stolen that crashed at high speed in South Auckland.
Harrison is desperate to see changes in the way police pursue fleeing drivers, particularly young people. She thinks a law change is needed.
"I would like some laws to stop these cops who are young and hyped up. I feel they are on some adrenalin rush, too, when they are chasing kids.
"The thing is it's risking people's lives … So please stop and think before you chase our kids.
"I know they are in the wrong, but we still want them home at night."
Friday's review, a joint effort by police and the Independent Police Conduct Authority, is the fifth review of pursuits since 2000.
Police wouldn't comment ahead of the latest findings.
Minister Stuart Nash said he supported the current policy but was "keen to see" the review.
"I do back the police to use their discretion in deciding whether to chase, whether to abandon, what course of action to take," he said.
"These are the men and women that are out there seeing this every single day and making the split-second decisions that they believe are in the best interests of our community."
The IPCA said when the review was announced in late 2017 that its purpose was to "better understand the pursuit environment, and to identify any current issues with police management of these events".
"All cases covered by the review are being analysed to identify common themes and issues and identify areas of good practice," the IPCA said.
"A more general review of all pursuits will enable both organisations to develop a better understanding of pursuits and the management of events.
"This will help to identify opportunities to improve police policy, practice and procedures."
Following a 2009 review, the IPCA recommended the policy was amended to provide clearer guidance to officers on when a pursuit should be started.
In 2010, an internal police pursuit policy review recommended formally introducing a search phase process for when officers lost sight of the fleeing vehicle.
It came after a lead pursuing officer unknowingly drove past the crash site that claimed the life of Vianne Shead in 2008 near Timaru.
The vehicle crashed 15 metres down a bank, killing Shead, who was a passenger.
Other recommendations included more staff training and limiting the number of vehicles involved in pursuits.
Pursuits - the facts
• Since January 2008 there have been 30,950 police pursuits.
• The number of pursuits has increased steadily each year for the past decade.
• During those pursuits, 79 drivers and passengers were killed.
• Others were also killed including innocent road users.
• Police figures show that pursuits are most likely to happen between 10pm and 6am.
• Crashes are more likely at night.
• The majority of drivers are young males and many are driving stolen cars.
• In most cases the driver was killed. In a significant number of crashes, multiple passengers also died.