"Data collected by police over the past 22 months shows 53 drivers were involved in fatal and serious injury crashes with blood alcohol readings of between 51 and 80 milligrams per 100 millilitres of blood,'' Mr Brownlee said.
Under the changes, the penalty for returning a positive test between 50mg and 80mg would be a $200 fine and 50 demerit points.
Testing positive to more than 80mg would remain a criminal offence.
"We know that drivers with a very high blood alcohol concentration, and recidivist drink drivers, are responsible for a much higher proportion of alcohol-related road fatalities. That is why we believe this fine-based approach at the lower end is most appropriate,'' Mr Brownlee said.
The change will bring New Zealand into line with Australia's legal alcohol limit of 50mg per 100ml of blood.
Alcohol Healthwatch director Rebecca Williams said the long overdue decision meant it could finally get on with the business of further reducing alcohol-related deaths and injuries on the roads.
"The research evidence is clear, the more alcohol in the system the greater the risk of being involved in an alcohol-related crash. It is also clear that impairment kicks in at relatively low levels of alcohol. It is important that all drivers are encouraged not to drink or at least limit their drinking to one or two before getting behind the wheel,'' she said.
Alcohol Healthwatch agreed that an infringement approach to offending between the new and old levels was the best way forward, saving an unnecessary burden on the court system.
The New Zealand Transport Agency welcomed today's announcement.
"Drink-driving inflicts a huge amount of pain and suffering on innocent road users, and this change sends a clear message to those who would put others at risk by driving drunk,'' said agency road safety director Ernst Zollner.
"Together with other recent changes including zero alcohol limits for teens and new penalties for serious and repeat drink-driving offenders this measure will make New Zealand roads safer for everyone.''
