Police have been stunned but delighted by the drop in arrests for drunken driving by teenagers almost a year after the zero alcohol limit was brought in for the under-20s.
Figures released by police under the Official Information Act show that in first nine months of the new law coming into force on August 7 last year, 3091 youths aged 15 to 19 were arrested for drink driving.
The figure for the 12 months before the law change was 6414 - tracking towards an "absolutely brilliant" change, acting national manager road policing superintendent Rob Morgan says.
The figures are even better on Waiheke, sergeant Peter Knight says.
In 2011 there were 110 cases of drink driving, of those 21, or 19 per cent, were aged under 20.
So far this year there have been 52 cases of drink driving recorded. Of those apprehended just five, or 9 per cent, were under 20.
Sergeant Knight says the drop in numbers by over half shows the island's younger drivers have grasped the new drink driving laws.
"The young people are now becoming the new teachers. As they are still young they can form a good habit that will flow on. Older people find drink-driving a hard habit to get out of."
Superintendent Morgan says the true benefit of the new law will only be known after an analysis of the number of road crashes involving alcohol and drivers in the 15 to 19-year age group.
"We would hope that is where it truly makes the difference," he says.
Youth drivers can be charged with drink driving for having the slightest amount of alcohol in their system. They risk disqualification, receiving demerit points, fines and even imprisonment depending on the breath test results.
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