Speeding accounts for more than half of all traffic offences - despite being a factor in only 15 per cent of injury crashes.

One in four injury crashes are caused by drivers losing control and driver inattention, followed by motorists failing to give way (21.8 per cent), alcohol or drugs (17.3 per cent) and speed (15.2 per cent).

Yet analysis of police data released under the Official Information Act shows that speeding makes up more than half of all traffic offences.

Alcohol and drugs, the second biggest factor in crashes, accounts for just 1.9 per cent of all traffic offences while failing to give way, the biggest factor, was just 1.5 per cent.


The disparity has led critics to question whether police are targeting speedsters - rather than poor driving, inattention or those under the influence - because they are easier to catch.

Superintendent Carey Griffiths, the national manager for road policing, said very drunk drivers, or drivers travelling at very high speeds, pose a very individual high risk, but are actually relatively low in number, "which explains why they do not feature as prominently in offences, but higher in crashes".

Drivers with lower breath and blood alcohol levels, or those who speed but at lower levels, posed less of an individual risk, but the frequency with which they offend is higher, he said. While most people understand the consequences of drink-driving, the impact of speed is not well understood.

Research showed that for every 5km/h over a 60km/h limit, the risk of a casualty crash doubles.

While speed was not always the key factor contributing to a crash, it plays a major part in the severity of injuries.

When asked why the number of offences for failing to give way or stop was so low, Mr Griffiths said most were detected after the crash had occurred.

Police did target high risk intersections, said Mr Griffiths, who noted that more than 4000 red light runners were caught in Auckland, Waikato, Wellington and Christchurch last year.

But that's just three in each city per day, said Stu Kearns, who spent 28 years policing roads. The police "perform poorly" enforcing road rules at stop signs, traffic lights and dealing with inconsiderate drivers, he said.

"To say offences such as failing to give way are 'detected after' a crash shows police are putting it in the 'too hard' basket because it's so labour intensive."

Driver inattention - a factor in 26.7 per cent of crashes - such as cellphone texting was a bigger risk than speeding or drinking.

"This area is well under-reported and under-enforced," Mr Kearns said.

AA spokesman Dylan Thomsen said there was an average of about five crashes each day in New Zealand that left someone seriously injured or dead and many involved people who weren't speeding or drunk.