Men are charged with drink driving at a rate three times higher than women, police figures show.

Numbers of charges provided by police reveal while both males and females show the same trends over the years, males are consistently charged with driving with excess breath alcohol at least three times as often.

Police and the New Zealand Transport Agency were reluctant to comment on what caused the gap, but University of Waikato psychology professor Samuel Charlton said part of it could be caused by men driving more than women.

"When men and women are in a car together, usually men do the driving, as when they return from an evening out," he said.


"Second, men, more than women, are more likely to be driving at night.

"Both of these are very broad generalisations, and probably related, but probably contribute to the statistics . . . in some way."

Figures stretching back about 10 years show at the highest, men were charged with drink driving almost four times more than women. This was in March of 2008.

But on average the ratio sits a little over three to one.

The largest spike was in 2009, when men were charged 26,469 times, and women 8308 times.

Charge numbers plunged from 2009 to 2014, when men were charged only 16,440 times and women 5335 times.

Police and NZTA were unable to say what caused this drop in charges, but numbers have gone up since then.

While NZTA couldn't say why males were charged so much more than females, director of safety and environment Harry Wilson said it was the reason drink driving advertising is targeted at them.


"Men, and young men in particular, are more likely than women to drive while impaired, and the waste of young life and potential wrought by drink driving is particularly tragic," he said.

"The fact that young men are a high risk group for drink driving is reflected in both crash data and in figures on charges and convictions for drink driving offences. Young men are more likely to drive while impaired than other demographic groups, which means more are caught by police and more are involved in crashes.

"This trend is not unique to New Zealand, and the situation is similar in other Western/OECD countries.

"This is also why road safety advertising in New Zealand is squarely targeted at young men. Where advertising does target women or older men it generally does so in their role as people who can influence the behaviour of the young men who are the highest risk group for drink-driving."

Drink driving is a factor in roughly one third of fatal crashes on New Zealand roads, he said.

Road policing operations manager Peter McKennie said police know impairment is one of the main contributors to death and serious injury on the roads.

"That is why it's a focus area for police and why we run drink drive checkpoints, breath test drivers who are stopped by officers, and reinforce not drinking and driving in our safety messaging.

"Our messages are clear; it is safest not to drive after drinking, and if you are in any doubt at all about being safe to drive – don't drive. Doing so puts your life and the lives of others at risk, and no one wants to share the road with people who are taking risks."