Last night, in a conscience vote, MPs voted 68 to 53 in favour of keeping the alcohol purchasing age at 18.
Prof Jennie Connor believed raising the age to 20 would have reduced the amount of harm alcohol was generating among young people, families and communities.
"I think it's profoundly disappointing for people in New Zealand, because we've lost an opportunity to improve the health and safety of young people.
"There is plenty of research to back it up."
She believed the options split the voting.
"The majority of MPs wanted to raise the age, but because there were two options for raising the age, the vote got split.
"I think it's unfortunate that it happened that way."
Hospitality New Zealand Otago president Mark Scully and Oamaru Licensing Trust chairman Ali Brosnan did not believe the country's "issues" with alcohol would be fixed by raising or splitting the age limit.
"We need to fix our attitude towards alcohol and the sale of cheap liquor ... I think people's personal responsibilities should be looked at," Mr Scully said.
"We need to make it illegal to be drunk in a public place and we need to put some consequences for it in place."
Mr Brosnan agreed, saying he believed the problems with alcohol lay outside his establishments.
Clutha Licensing Trust chief executive David Kenny said a split age system would have been difficult to control, especially in rural hotels: "It had to be one age or the other.
"Eighteen-year-olds are going to drink any way. I would rather it was in a controlled environment than out on the street."
Two Dunedin 18-year-olds were not surprised at the way the vote went.
"I don't see the point in putting it up to 20. If you're 18, you're just going to find someone who's 20 to get it for you," Bryan Dowell said.
Mikey Khalifa agreed.
"It would have just made more criminals. It wouldn't have stopped underage drinking.
"It's ridiculous. You can join the army or go to jail at 17," he said.
Justice Minister Judith Collins said keeping the purchasing age at 18 across the board denied one effective way of curbing problem drinking, but it was not the only tool available.
"Our Alcohol Reform Bill aims to drive lasting change to our drinking culture, and has a wide range of measures to reduce alcohol-related harm in our families and communities.
"But, we can't do it alone. We all have a role to play in shifting our drinking culture towards more moderate and responsible alcohol consumption," she said.
Labour MP Lianne Dalziel started the debate on the Bill, saying the focus on the purchase age was distracting attention away from other important issues.
"If anyone thinks that by changing the age that we have solved the problems this country has with alcohol then think again because we haven't solved the problems at all."
National MP for Hamilton West Tim Macindoe urged MPs to support his supplementary order paper to restore the minimum age for all categories of liquor purchases to 20 years of age.
The debate was not a matter of blaming young people for New Zealand's binge-drinking culture.
"It's about trying to protect them from it. It isn't about restricting their rights; it is about enhancing the rights of those who love and care for them to guide them in safe and responsible choices as they move into the adult world," he said.
New Zealand First MP Denis O'Rourke said he would prefer seeing the drinking age raised to 21 but would vote to raise it to 20.
It was also not logical or credible to distinguish between an on-licence and an off-licence premises as far as age was concerned.
"The split age is not a good compromise - it's just a cop-out," he said.
National MP Tau Henare urged the House "to lay off the young people".
Supporting an age of 18, he said 18-year-olds were entrusted with voting and defending New Zealand or other countries in armed conflicts.
"But they can't have beer? Give me break," Mr Henare said.
Green MP Kevin Hague said there was no evidence to support a split age. It would have enforcement problems and would force new drinkers into licensed premises, "where their role models ...will be the dysfunctional drinking culture of the rest of us".
"Thirteen years ago, the purchase age for alcohol in this country was reduced from 20 to 18. Within a few years it became obvious that, although the new freedom was very popular amongst teenagers and the alcohol industry, the alcohol-related harm to teenagers had increased."
The age at which alcohol can be bought was the first part of the Alcohol Reform Bill to be debated. The remaining committee stages of the Bill will progress through the House as time becomes available.
Key proposals to reduce alcohol-related harm include increasing the ability of local communities to have a say on alcohol licensing; strengthening rules about the types of stores eligible to sell alcohol; and restricting supermarkets and grocery stores to displaying alcohol in a single area.
Requiring express parental consent for the private supply of alcohol to those under 18 and ensuring the alcohol is supplied in a responsible manner; restricting alcohol availability by making it harder to get a licence; introducing maximum trading hours for licensed premises; and strengthening the controls on alcohol advertising and promotion, by making it an offence to promote alcohol in a way that has special appeal to minors, are other measure proposed.
- Additional reporting APNZ
The options
Aged 18: for drinking at on-license premises and buying liquor from off-license premises.
Aged 20: for drinking at on-license premises and buying liquor from off-license premises.
Split age: 18 for drinking at on-license premises and 20 for buying alcohol at off-license premises.
The vote
To split the age: First option to drop off the ballot - age 18 age option (50 votes), age 20 option (38), split-age option (33).
Final vote: 68 for age 18, 53 for age 20.
