Under limit after 13 beers in 2 hours

The police said a person who drove to the 50mg limit was six times more likely than a sober person to crash. Photo / APN

A senior police officer who drank 13 beers in two hours and remained under the legal drink-driving limit as part of an academic study says lowering the limit would save lives and reduce injuries.

New Zealand police officials told a select committee at Parliament yesterday that by the time a person drank the legal limit of 80mg of alcohol per 100ml of blood, they were no longer fit to make a decision about whether they should drive.

Their comments came as a two-year study on drink-drive limits wrapped up. Ministers will be given a report by the end of the year which reveals how many injuries and deaths were caused in the past two years by people who had between 50mg and 80mg of alcohol in their bloodstream.

Australia introduced a 50mg blood-alcohol content (BAC) limit more than 20 years ago.

Labour MPs asked police officials yesterday if there would be a significant difference if New Zealand made the same change.

Assistant Commissioner Dave Cliff said overseas studies indicated that between 10 and 25 deaths, and hundreds of injuries, would be prevented if the lower limit was introduced in New Zealand.

"Without exception, every jurisdiction showed significant reductions in alcohol-related trauma as a result of that move, so we would expect to see the same effect in New Zealand," Mr Cliff said.

"The research says that when you reduce BAC level, the whole distribution of offending moves to the left, so high-end drinkers drink less, the risk declines across the whole population - that's the impact you see."

Road policing manager Superintendent Carey Griffiths said many New Zealanders would be surprised by how liberal New Zealand's drink-drive limit was.

He said he had consumed 13 beers in two hours as part of a study and was still below the 80mg limit.

"There's no way you would ever drive. It was an extraordinarily large amount of alcohol to be under the limit."

National MP Mark Mitchell, a former cop, spoke of drinking four bourbon and cokes and testing himself to find he was still under the limit. "I was in no fit state to drive," he said.

The police said a person who drove to the 50mg limit was six times more likely than a sober person to crash. A person who consumed 80mg was 16.5 times more likely to crash.

Police said Sweden had a legal limit of 20mg per 100ml, and its road trauma rate was nearly half New Zealand's in terms of deaths per 100,000 people. A blood-alcohol level of 20mg was roughly equivalent to two drinks for an average-size man.