"A drug and alcohol expert from the United Kingdom has estimated that this measure could reduce our road toll by two-thirds as it would alter driver behaviour," the bill says.
Dr Farrell supported the implementation of the lower limit but would have preferred to set even lower alongside other recommendations issued by the World Health Organisation to curb alcohol-related harm.
"The important thing is as a precautionary principal you should have your drink driving limit below the level that is medically defined as drunk.
"Alcohol is one of the few drugs that has massive double standards around it. It causes cancer and yet it's not labelled; it's considered something you drink with gay abandon in New Zealand even though it has the same safety ratio as methamphetamine.
"What it will do is reduce problem drinking and that will result in a lot less harm from cancer, heart disease, depression and 60 different conditions, so it's a great move.
"It's estimated that 20 per cent of GP consultations relate to alcohol. A person coming in with a flu on a Monday may in fact be hung over."
Senior roading police recently told the Law and Order Committee that lowering the limit overseas had reduced road trauma without exception.
Doing so here would save between 10-25 lives a year in New Zealand, the committee heard.
Western Bay of Plenty road policing manager Ian Campion preferred not to comment on the proposed change while it was still moving through Parliament.
Statistics were not kept on how far over the limit the average drink driver was at the time of their arrest, with Mr Campion stating offenders recorded readings covering the entire spectrum.