Reefer-endum? NZ's marijuana decision and Australia

"It will have an impact here [if the yes vote succeeds] because of the close ties between the two countries. If they move down a pathway that we think is fairly sensible it will raise the need to review what we are doing here," he said.

"At the very least we hope it sparks some discussion about what we are actually doing with our drug laws. New Zealand may also end up attracting more Australian tourists too [if legalisation occurs]."

Under the proposed legislation, which would be brought to Parliament if the 'yes' vote succeeds, it would become legal to grow your own cannabis or to buy up to 14 grams of dried cannabis from a licensed dealer per day.

Consumption would have to take place in the home or at a licensed premises – which would also be licensed to sell food in the event that customers are hungry.

The legal age for purchase and consumption would be 20, and users could share cannabis with friends but would not be allowed to send it by post or sell it to others.

Aaron Ironside, the spokesman for the Say Nope to Dope campaign, said his organisation supported medical marijuana and recent legal changes to the Misuse of Drugs Act that instructed police to focus on people who sold and distributed the drug, rather than casual users.

The organisation opposed legalisation because it did not protect young people who were particularly vulnerable to the health risks posed by use of the drug.

Cannabis does cause harm ... Why do we think that organised crime is better placed to manage cannabis?

Ross Bell, executive director of the NZ Drug Foundation

"It doesn't stop them [young people] from buying on the black market – therefore the law doesn't accomplish its goal," he said.

That's because, Ironside said, the proposed tight regulations on the profit a grower or seller could make from a $20 gram of the drug – and harm minimisation tax that would be imposed – meant it would still be more profitable to sell the drug on the black market.

"14 grams a day is a lot. It's like saying we are going to control alcohol consumption by limiting people to three bottles of vodka per day."

Executive director of the NZ Drug Foundation Ross Bell said the current prohibition on the drug had simply not worked and "it's time for a different approach".

"We are convinced the law will protect public health much better than leaving cannabis in the hands of organised crime. Cannabis does cause harm and we know particularly that harm falls heavily on young people. Why do we think that organised crime is better placed to manage cannabis?" he said.

"The law we are voting on is all about protecting young people. One of the problems with prohibition is it criminalises people and it also puts up a barrier to people seeking help as it becomes a criminal issue."

Polling on whether a majority of New Zealanders will vote 'yes' or 'no' is not definitive but indicates the move to legalise the drug could be defeated.

Respected pollsters Colmar Brunton has found in four polls conducted over the last two years the 'no' vote attracting between 49 and 52 per cent of the vote, while the 'yes' vote has attracted 39 to 43 per cent support and 'undecided' voters have ranged from 7 to 11 per cent.

However, polling by Research New Zealand has suggested the contest is closer, while a poll taken in late August by Horizon research – which was commissioned by medicinal cannabis company Helius Therapeutics – showed the electorate was evenly split 49.5 per cent to 49.5 per cent.

A cautious Ironside was careful about predicting the outcome of the vote but said "the indications are the message is out there and getting through, and we hope New Zealanders make the right decision".

Bell, for his part, was similarly cautious and added that "every vote counts, including from the many Kiwis living in Australia who can vote. We hope they can shape a better New Zealand too".