Asked to vote with their conscience on whether the drinking age should be raised, the nation's MPs responded in a way that revealed the unpredictable undercurrents at play in the national debate on alcohol.
As the vote progressed, it became clear party affiliations meant nothing and easy categorisation could be thrown away. In the end, it was a guessing game to see who would go for which option - keeping the purchasing age at 18 or returning it to 20, the age at which most of the MPs voting would have been legally allowed to buy their first drinks.
A number of Green MPs, known for their support in pushing legislation to improve health, voted to keep it at 18. In the opposing ideological corner, some National MPs, whose party preaches the virtues of personal responsibility, stood up and argued passionately for teenagers to have the right to buy booze taken away from them.
Some MPs used research to back their argument. Others argued more at a gut level, pointing out teenagers who can go to war for their country should be entrusted to have a beer.
The issue was clouded by a third option to have a split purchasing age - which skewed the result. It seemed an idea with merit - and MPs polled by the The New Zealand Herald last year indicated it would be their preference - but it fell at the first hurdle and may have had the effect of splitting the final vote.
Prime Minister John Key, who has resolutely come out against minimum alcohol pricing, showed his love of a good compromise by supporting this proposal and later said he was disappointed it had not passed.
Others who were disappointed after the vote were health experts such as University of Otago's head of preventive and social medicine Prof Jennie Connor, who described retaining 18 as the alcohol purchasing age as "profoundly disappointing".
Prof Connor, who will have been been exposed to the more extreme results of binge-drinking among young people on the streets around the university's North Dunedin campus, said research showed raising the age would have reduced alcohol-related harm. Her views are doubtless shared by many hospital emergency department staff, ambulance officers, beat police and others on the front line of the weekend mayhem.
Polls on news websites since the vote have shown a clear preference for raising the age.
Despite the evidence cited by Prof Connor and others, the 68-53 vote to keep the age at 18 demonstrates a reluctance among lawmakers to view alcohol solely through the lens of detrimental health impacts. This was illustrated when National MP Mike Sabin told Parliament there was clear evidence that the developing brains of 18-year-olds were particularly susceptible to alcohol, but his message did little to sway the vote.
Nobody is suggesting a moderate use of alcohol is in the same neighbourhood of health risk as, for example, tobacco. But we now know there is resistance among MPs to start down the road of legislating on this basis. At this point, the "in moderation" card trumps all.
So, did the MPs get it right or wrong?
In answering that question, the suite of initiatives being proposed under the Alcohol Reform Bill have to be taken into account. The nation as a whole - not just the 18 to 20-year-olds - needs an intervention and it can be argued among these proposals, and further initiatives they might spark, remains a workable road map.
National MP Tim Macindoe, who tabled the amendment to raise the purchase age to 20, says he remains confident the rest of the Bill - with, among other measures, proposals to ban alcohol advertising targeting young people - can make a difference.
Health experts such as Prof Connor are not so sure.
Lawmakers must ensure they remain open to the evidence as it accumulates and be prepared to revisit abandoned proposals.
In a wider sense, all adult New Zealanders have to be involved in solving our drinking problem.
Sadly, raising the age would not have automatically raised the level of maturity New Zealanders bring to our battle with the booze.
