Sixteen people have died this year after vehicle pursuits by police. The toll has renewed high-level pressure on police bosses to review pursuit policy .

All 11 fatal police pursuits this year arose from traffic infringements, putting pressure on police to tighten pursuit policy.

An international expert in police pursuits says New Zealand's policy which enables high-speed chases for minor offences is 20 years out of date.

A police review of pursuit policy this year - the fourth in six years - ignored key recommendations of the Independent Police Conduct Authority (IPCA) and made only minor changes.

The rate of fatal pursuits has since risen. Eight people have died in four pursuits since June, when Police Commissioner Howard Broad announced that an internal review of police pursuits had found the policy needed only minor tweaking.

IPCA chair Justice Lowell Goddard called Broad and deputy commissioner Vic Rickard to separate meetings last week at which she pressed them to continue to review pursuit policy. The meetings were held on Monday, three days after two people died after a chase through Onehunga.

A Weekend Herald review shows 16 people have died this year in connection with 11 incidents, all arising from relatively minor offending such as speeding. That appears to make this the blackest period for police pursuit fatalities and a huge increase on the rate for previous years.

The IPCA studied 137 pursuits that were reported to it in the five years to December 2008. It found 24 people had died in those pursuits and only 31 pursuits had started over known or suspected criminal offending.

Goddard last year called on police to more clearly proscribe when to pursue and to make "the risk to public safety from not stopping an offender" the main consideration.

The Authority also recommended that the decision to pursue be based on known facts, rather than general suspicion or speculation.

Neither recommendation was taken up. Goddard yesterday told the Herald the IPCA stood by those recommendations and believed public safety issues were of sufficient importance to merit ongoing review of police pursuit policy.

She said the top two police officers had agreed to further discussion.

Road safety campaigner, the Candor Trust, says police pursuits have increased five-fold in the past seven years to 2500 last year.

Spokeswoman Rachael Ford says this reflects a willingness to chase relatively minor offenders which Candor believes is driven by a quota system on ticketing speeding and drink-drivers.

But Inspector Rob Morgan, acting national manager of road policing, says the jump in pursuit fatalities this year has not persuaded police to review a policy which gives discretion to chase relatively minor offenders.

Morgan notes that 23 per cent of pursuits last year were of stolen vehicles and therefore of criminals.

"Police haven't changed their view and the number of fatalities, while tragic, do not change the picture as such," says Morgan. "It's a bit random whether a fatality occurs at the end of a pursuit." Police couldn't manage the outcome other than deciding not to chase.

Officers do assess the risks of pursuit (the primary principle is that the seriousness of the threat ultimately determines the police response) but must do so in real time. The pursuit in Onehunga lasted little more than two minutes and, says Morgan, in the previous incident (Christchurch, two killed) the officers "didn't even have time to call it [the pursuit] in."

Of this year's 11 fatal pursuits, six were sparked by speeding drivers, one by a driver doing burnouts, one by the refusal of an evidential blood test, one by a driver fleeing a routine stop and, in the latest, police chased a car from which an laser was suspected of having been flashed at motorists.

Morgan: "Our position here is that police have no intention of handing the roads over to those who think they are above the law, and offenders who flee from police put themselves and innocent road users at risk and will be subject to the full pressure of our resources and will be held to account for their actions."

Police will push for harsher penalties for those who refuse to stop.

The Herald asked Geoff Alpert, a South Carolina University criminology professor who has specialised in pursuit policy for 25 years, whether police in that part of the world would have chased in the case of the laser incident.

"Some departments, yes; many departments, no," says Alpert who is a consultant for police in North America. "The line I draw in the sand is a violent crime and obviously the traffic offence, the laser, wouldn't amount to that."

In instances where they know who the driver is, police have other options. The registration plate can be sufficient, says Alpert. The term is "rebuttable assumption" - if the registered owner claims not to be the driver but refuses to divulge who was behind the wheel then the owner is charged with the offence.

"What's happening in New Zealand is what happened in the United States and Canada probably 20 years ago in that police were given broad discretion to make independent decisions about pursuit driving."

In the past decade that discretion has been "restricted drastically" in North America. "That's because of the deaths and injuries and enormous financial expense that occurred when chases went bad," he told Radio New Zealand - and in the US and Canada they had often gone bad.

The trend was to restrict pursuits to violent offenders with police using other means to catch technical or traffic offenders and in some districts, property offenders.

"The number of crashes and severity and injuries had increased so much, these offences are not considered worth the risk of a chase in our crowded streets."

The justification for police deciding only to tweak pursuit policy is summed up in this statement from its latest review, a view shared by the Police Association which represents rank and file officers: "If criminals know that police will not pursue them, or have so many restrictions placed on them it renders pursuits futile, then the job of police to uphold the law not only becomes difficult, but almost impossible."

That's not been the experience in North America, says Alpert: "There are two myths. The first is that there is a dead body in every trunk. That means everyone who runs from the police has committed a serious crime and that's just not true.

"The other myth is that if you don't chase everyone then everyone will run from you. We know statistically from studies on many departments that that is not true. There is a sub-culture of people who are going to run no matter what, but most of us don't."

Public opinion regarding pursuits has changed in the United States, he says. "The more the public knows about the consequences of pursuit, the less they support it for minor offences. I don't think it has changed for serious violent crimes."

Last month Deidre Jordan, 67, and Norm Fitt, 73, were killed when their vehicle was hit by a car driven by 22-year-old Phillip Bannan, fleeing police. Police later said Bannan was "known to police". The pursuit, however, began because Bannan was speeding.

The Christchurch fatalities prompted Christchurch area commander Inspector Malcolm Johnston to appeal to drivers to stop fleeing police.

"They don't have the right to take innocent lives like this," Johnston said. "They don't have the right to take other road users' lives. All this driver had to do was stop. We don't know why he chose to try to run from the police."

True, says Alpert, "if only the bad guy would stop." But we don't live in a perfect world. We know some people don't stop. We have to prepare for the bad guy not stopping and make our decisions before it occurs, so officers know what to do.

"It's descriptive when they talk about the fuel behind the rocket. Clearly the fleeing suspect is the rocket but often the police officer can be the fuel."

Deciding not to chase can go against the grain for police officers who want to do their job and the public a service by catching the bad guy. It comes down, says Alpert, to policy and training and understanding the consequences, that the chasing is often a factor of a fleeing suspect crashing into innocents.

"It's very difficult for police officers to understand that often the best thing for public safety is that some people have to escape."

Placing all the blame on the fool who flees is not best practice, says Alpert.

"Any kind of a pursuit plan includes policy, training, supervision and accountability. You have to hold the police officers accountable for their decisions and you have to hold the police chiefs accountable for their decisions."