Supporting a regulated market for cannabis hardly requires you to think cannabis is a good thing. It rather recognises that illegal markets are risky with their own harms, and that American states that have liberalised have generally seen good outcomes. Regulated legal markets bring the protection of the Fair Trading Act and the Consumer Guarantees Act. Criminal profits transform into government excise earnings.

Labour’s agreement with the Greens promised a referendum on legalising the personal use of cannabis at or before the next election.

But what would that mean? The referendum could ask whether people be allowed to grow one or two plants for personal use, maintaining prohibition elsewhere. It could propose removing cannabis from Schedule 2 of the Misuse of Drugs Act and treating it the same way as any other consumer product. And there are no small number of options between those poles.

Next week, the Cannabis Referendum Conference will start hashing out what legalisation should look like. The Greens’ Chlöe Swarbrick will talk about the recent medical cannabis campaign before joining a panel with Labour’s Ginny Anderson to discuss the coming referendum on personal use. Former Prime Minister Helen Clark will appear by video conference.

And Labour’s Greg O’Connor will be there talking with me about models used abroad, his recent travels to places like Switzerland, and Canada’s legalisation of cannabis this past month. 

Canada’s marijuana legalisation piggybacked a bit on the country’s varying provincial rules for alcohol. Provinces have different minimum drinking ages; minimum purchase ages for marijuana were left to the provinces. Some provinces limit alcohol sales to provincial government stores; provinces were left to decide whether cannabis sales should be through private stores, government stores, or both. Excise of $1/gram applies everywhere.

New Zealand could do well by simply adapting for cannabis the rules already in place for alcohol – like minimum purchase ages, provision for local cannabis policies that vary from a national default, and restrictions on advertising and marketing.

Referendum questions should ask voters to approve a finalised piece of legislation. Even questions that seem straightforward can turn thorny in the political debates around a referendum – the referendum on legalising spanking was not that long ago. Two years is a long time for thinking about a referendum question but is not all that long for setting legislation.

Hopefully, next week’s conference will help start the ball rolling.