Police use doubtful science to justify rigid speed enforcement

The police ignored basic road safety science when they decided to rigidly enforce speed limits, says the car review website dogandlemon.com.

Editor Clive Matthew-Wilson, who is an outspoken road safety campaigner, says:

“The vast majority of fatal crashes occur below the speed limit. Few speeding crashes are caused by ordinary motorists. However, if ask the average policeman to name the biggest safety threat on our roads, they’ll probably say ‘speed’. They’ll also tell you that the police need to rigidly enforce speed limits in order to save lives.”

"In fact, neither of these statements are even close to true.  Speed is the primary cause of just 15% of fatal crashes,  according to a Ministry of Transport document.”1     


“’Speed kills’ is a great slogan, but it’s far too simplistic. For example, the Waikato Expressway has a speed limit of 110kp/h, which is 10kp/h higher than the average highway speed limit. So, the Waikato Expressway should be a killing field. In fact, the Waikato Expressway is one of the safest roads in the country.

“Another inconvenient truth is that the police are targetting the wrong drivers. As a matter of scientific fact, few ordinary motorists cause speed-related fatalities. Almost all speed-related fatalities are caused by a small group of yobbos2 and reckless motorcyclists, and they’re often blotto when they crash. Yobbos and blotto drivers don’t read speed signs, rarely think of consequences and are effectively immune to road safety messages.” 

A 2009 AA study of 300 fatal crashes concluded:

"government advertising suggests you should be grateful to receive a speeding ticket because it will save your life. In fact, exceeding speed limits aren’t a major issue. Only one in six fatal crashes were reported over the speed limit – and they were well over. Nor is it true that middle-New Zealand drivers creeping a few kilometres over the limit ... dominate the road toll. [Instead, the main culprits in speed-related accidents were] people who don’t care about any kind of rules. These are men who speed, drink, don’t wear safety belts, have no valid licence or WoF – who are basically renegades. They usually end up wrapped around a tree, but they can also overtake across a yellow line and take out other motorists as well."

Matthew-Wilson gave the example of Cameron Presland (20). In 2014, Presland killed his girlfriend Danielle Kiriau (17) and her brother Shannon (22), while driving between 142kmh and 163kmh. The pair were passengers in Presland's unwarranted, unregistered, modified vehicle, which spun out of control on Dunedin's Southern Motorway and crashed into a metal pole.

“Perhaps the police could explain how ticketing ordinary motorists going 1k over the speed limit would have prevented this crash?”

Matthew-Wilson also gave the example of Jeremy Thompson, 28, who caused a head-on crash near Waverly that killed seven people in 2018. Thompson had been smoking synthetic cannabis before the crash.

“Again, perhaps the police could explain how ticketing ordinary motorists going 1k over the speed limit would have prevented this crash?”

Matthew-Wilson says one of the most tragic examples of reckless driving was James Solvander, who was on drugs and carrying firearms when he hit and killed a father and daughter out cycling.

"Solvander was already wanted by the police and undoubtedly knew that police were likely to be patrolling the road as he drove, but this made no difference to his behaviour."

“The current police anti-speeding campaign will never lower the road toll, because it’s targeting the average motorist rather than the high-risk groups. That's like trying to stop bank robberies by targeting shoplifting."

“Few drivers have a problem with the police enforcing speed limits; that’s not the issue. However, it’s frighteningly easy for innocent drivers to drift over the speed limit. Unlike Australia, where speed limits are constantly displayed along highways, you can travel down many New Zealand roads for many kilometres without any signs telling you what speed you’re supposed to be doing. Often the speed limit changes with little more than an easily-missable sign at the side of the road. The police blindly issuing thousands of tickets to relatively innocent drivers will simply alienate motorists without solving the main problem.”


Matthew-Wilson  favours speed advisory signs, which simply show motorists what speed they’re doing, without issuing a ticket.

Speed advisory signs are highly effective at lowering speeds in high risk zones, but they don’t alienate motorists. The fact is, most ordinary drivers will slow down if you remind them that they’re going too fast.  The police can then wait around the corner and ticket those who don’t take the hint.”

“That’s how they do it in Sweden, which has the world’s lowest road toll; they give drivers a chance to do the right thing by warning them first. That’s the way to get the support and cooperation of the average driver.”

Matthew-Wilson adds:

“The Covid-19 crisis has shown the importance of public trust in the fairness and impartiality of the police. Misguided policies such as this one are likely to cause irreparable damage to the public’s faith in the police, without dealing with the real causes of most speed-related road deaths.”


1* Source: Alcohol and drugs crash facts, MOT, 2017, page six. Please note that the graphic we display is slightly different to the version in the MOT PDF. This is because the original graphic no longer appears to be online. However, the graphic we display in this release is an exact facsimile of the original, with the exception of the date, which in the original read 2014-18, not 2014-16. 

The police (and now often MOT and NZTA) prefer to quote their own subjective figure that “travelling too fast for the conditions was a contributing factor in about a third of all fatal crashes.” Even accepting accepting this rather vague own-statistic, the police are effectively stating that the vast majority of fatal accidents (two-thirds) do not involve speeding.

2* Young, poorly educated males with anti-social attitudes, and those who associate with them. Most grow out of their anti-social attitudes. Those that don’t remain a high risk throughout their lives.