2. What does legalising cannabis mean?

Whether cannabis should be legalised seems simple, but it comes with a whole lot more questions.

One of the most immediate would be how commercial the market should be. If cannabis can be bought and sold, would it be a state-controlled market or a commercial one?

Would it mean cannabis becomes legal to buy from a store? Would it be legal to grow your own?

One of the benefits of legalising cannabis is the state profiting from tax on the product. The Government would need to work to find the right level of taxation. Too high and the black market would be tempting. Too low and marijuana might be too accessible.

3. Do we want a market like alcohol or like cigarettes?

The risk of commercialisation is a powerful new industry could be created.

There are nearly a dozen different options for legalisation regimes that aren't profit-driven and commercial says Chris Wilkins, leader of the drug research team at Massey University.

"It's really crucial that when we talk about legalisation that people don't think the only option is creating a commercial market like alcohol - a profit-driven market where you have a little bit of regulation."

Where alcohol is loosely regulated, tobacco is much more tightly regulated, Dr Wilkins says. Placement, packaging and price is all much more heavily regulated for tobacco.

Dr Wilkins says an example of a market that's not commercial would be a Government monopoly where the Government restricts advertising and the money goes back to the Government, or public trusts that return money to the community. Pokies trusts have to return 40 percent of their profits to the community.

"If I was voting in the referendum, I would want to know that detail."

4. How would communities be kept safe?

Communities will be worried about cannabis being sold near schools, churches and cultural institutions, so decisions will need to be made about where the product can be sold - and whether local government has a role in those decisions.

There would need to be an age limit. In Canada it's the same as the drinking age, which is decided state by state.

If it was 18 in New Zealand, that would mean kids in their last year of school could legally smoke it. How would schools deal with that?

The Drug Foundation says the ideal age limit would be 25, but says that's an "unrealistic goal" and it's more practical to keep it the same as the alcohol limit.

Then there's driving - what would the law be around that?