This week, which is completely coincidentally also 4/20, the Greens announced they will push for the legalisation of cannabis in Australia. "The war on drugs is a war on young people," party leader Dr Richard Di Natale told a press conference on Thursday. The response from the major parties was, simply, a hard no. Government health minister Greg Hunt labelled cannabis a "gateway drug." Labor leader Bill Shorten said his party is focused only on medical cannabis, and even went so far as to call Di Natale's announcement a "headline grab."

So are the Greens serious about legalising cannabis in Australia? Or is this just the stoner version of that bullet train from Melbourne to Sydney, which comes up every time there's an election on the horizon? A "headline grab," if you will.

VICE called up Greens party leader Richard Di Natale to have a chat about all this. What quickly became clear is that this policy is still in its infancy. The Greens know they can't change this law without the support of at least one of the major parties—and so concrete details are hard to lock down. But here's what we know: the party thinks the government should act as a wholesaler and sell to retail stores, people should also be allowed to grow up to six personal plants, and there's a lot of tax revenue to be made here.

It also seems this policy is largely grounded in reforming the criminal justice system, rather than just health—as much drug law reform is in Australia. Both Di Natale and Dr Mehreen Faruqi (of the NSW Greens) told VICE they would support setting aside old criminal convictions for personal cannabis possession, a topic that's been a hot debate in the US and Canada.

Hi Richard, thanks for taking the time to chat. Let's jump into it: Bill Shorten called your push for cannabis legalisation a "headline grab." Is it? It is 4/20 this week, after all.

Richard Di Natale: First thing, Bill Shorten is wrong. It has not been Greens policy. In fact, this is the first time we've ever announced it, nationally. His statement was wrong... our policy up until a couple of years ago was that we did not support the legalisation of any current illegal drugs. That has changed, and it was a change I advocated for very strongly within the party, knowing that at some point we did need to have a national conversation about legalising cannabis.

So you reject that this is a headline grab?

No, this is actually sensible policy. It's a shame that Bill Shorten—rather than playing silly policy—won't just listen to the experts. He isn't prepared to have an adult conversation about how we respond to the fact that so many Australians are using cannabis and, right now, they are receiving criminal recourse for making that choice.

Okay, so where to from here? If you're really serious about this, talk me through the steps from today to the day cannabis is legalised in Australia.

Well, first thing, the Greens are going to keep campaigning on this issue and continue to build support for it. We know that the majority of the community do support it. Poll after poll has showed that most Australians support the taxation and regulation of cannabis—taking it away from dealers and criminals. So, we'll continue to campaign on it. The next step for us is to look at what the legislation at both the state and federal level is necessary to give effect to these changes.

That's something I noticed a few people brought up after your announcement—whether this could be done at the federal level or if you have to get the states on board. What about the other parties though, can the Greens do this alone?

Ultimately, we realise that it's necessary for one of the major parties to adopt it. And for those parties, when they are in government, to implement it. There are opportunities though: the Greens demonstrated back in 2010 where we had a number of issues that we put to the government in the event of a hung parliament to try and force their hand and implement government policy. So there are always opportunities to implement government policy. The other thing to say is that we've campaigned on a number of issues that have become either government policy or opposition policy. I look at marriage equality as an example where for more than a decade, in fact almost two decades, we continued to campaign for marriage equality and it was a campaign we ran with the community through state and federal parliament and worked hard to build a constituency so that ultimately the pressure became overwhelming. And what we saw was obviously after a long and tortuous process, marriage equality passed into law. There are lots of other examples, medicinal cannabis is another one.

It felt like medical cannabis went from "no" to "yes" so quickly.

Medicinal cannabis is problematic though. The government has introduced legislation and it was nowhere near good enough. But you're right, it was only a few years ago when they promised they wouldn't do anything, and Labor was in the same position. Labor and the government steadfastly refused to make any changes to legislation to allow medicinal cannabis. I worked across party lines, and members of the Liberal, Labor, and national party came together in a working group and we developed joint legislation that we put to the parliament. Ultimately what happened is that the government decided to introduce its own legislation, which is—as I said—still inadequate. But it does demonstrate what you can achieve by building pressure from within the parliament. Again, I'll be looking for allies from all sides of politics so they can champion this reform through parliament and hopefully from within their own parties. I just think it's only a matter of time before it happens.

You mentioned medical cannabis and I think a big part of shifting the national conversation about that was Dan Haslam. His bravery is sharing his story, before he passed away. Who is going to be "the face" of recreational cannabis?

What you've seen is a number of voices have come forward now through this debate. People from law enforcement—I think Mick Palmer has been a really strong and powerful voice. When the former commissioner of the Australian Federal Police comes forward and says, "We need to change." There are doctors, people within the medical community who've come forward. Obviously Alex Wodak is one of those. People within the legal professional, we've seen Greg Barnes be very vocal on this. But obviously, one thing that is missing right now is the user perspective and a voice from young people, but those people, over time, we be I think important in the debate. If you look at the way the history of these reforms played out overseas it wasn't because of one person, or one individual. It was about building a broad coalition of different groups who came together and advocated for the reform and I think that's what has to happen here in Australia.

So why legalisation and not decriminalisation, which may have been easier to get across the line?

We do support decriminalisation. In fact, I went to Portugal a few years ago. The Greens' drug policy is to remove criminal penalties associated with use of all drugs. So we already have a policy when it comes to personal use of drugs and believe people shouldn't be subject to criminal penalties. But within decriminalisation, the black market still operates—the sale of products that are of unknown quality and purity continues. Criminal syndicates continue to make mega profits... Legalisation takes it out of that framework, and puts it within a controlled and regulated environment. What it does is give people the confidence to know what they are purchasing is relatively safe, the products are not contaminated, and that the products are strains that are lower risk strains. It also means that people who do get into trouble with their drug use aren't seeing a drug dealer but are actually seeing a trained professional who can provide advice about the kind of support that people need. It has so many benefits.

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The head of the Australian Medical Association (AMA) came out against your plan based on research about the negative health effects of cannabis. You're a doctor, I'm sure you've read the research on this. Where do you come down on the link between smoking weed and mental health issues?

There's a few things to say. I think it's important to note that there are many doctors who support legalisation. The AMA doesn't speak for all doctors, in fact, it may not even speak for most doctors. The AMA does support removing criminal penalties. It's very critical of the current system of having users of a drug subject to criminal sanctions, which is still the case in many states. In terms of the actual research around the health impacts of cannabis, the research around the link between mental health and cannabis is complex. What we do know is that if somebody does have an underlying mental illness, then cannabis can exacerbate the condition, and that's not really contested. But there is still debate around whether cannabis is causative, whether cannabis is the cause of mental illness. We know many people self-medicate. So we know that many people who are suffering from the early signs of mental illness—be that anxiety or depression—will use cannabis and that cannabis may exacerbate, rather than alleviate, those symptoms. It might provide some short term relief but over the long term, particularly with chronic use, it can make those symptoms worse. The bottom line is that's happening already though. Some people will argue that you shouldn't move to a legal framework because of those things, what we're seeing because it's illegal is that for those people with a mental illness the current system makes the problem worse. What's the incentive for a drug dealer to provide support to somebody if they're misusing cannabis? There isn't one.

Cannabis has already been legalised in Uruguay, Canada, and several states in the US—a country that is, in some places at least, so much more conservative than Australia. Yet Australia seems so far away from even thinking about legalising recreational cannabis. Why are we so far behind?

I wouldn't say Australia is behind, I'd say our politicians and the corporate media are behind. If you actually ask Australians, poll after poll has shown that they are behind this change. It's really important to make the distinction between what ordinary Australians think and what the political class and the corporate media think. They are very different things. In fact, it just shows how out of touch politicians are on so many issues. It is true that the response [from government] was, "We're not going to do this." But let's remember, that was the initial response to medicinal cannabis, that was the response to things like marriage equality. In Victoria, we've just assisted dying legislated and for many years—in fact the Premier himself ruled it out... it's a process, and you need to start the conversation.

Okay, what's the biggest roadblock to making this happen?

I think we've got a political class in this country that's captured by vested interests that doesn't have the courage to lead. That is not prepared to make some difficult decisions. When one of the major parties shows some leadership on this, I think they will benefit. But, right now, we've got two political parties that are intent on being small targets, who aren't interesting in taking on the corporate media, and are afraid to lead. That's why we are where we are. But that doesn't mean it won't happen, I think it will. I think it's a matter of time, and I think what we've started is a really important conversation.

Let's lock down a date then. When is cannabis going to be legalised in Australia.

Yeah, I think there's no reason why we couldn't get this done in a year. Again you just look at what happened with physician-assisted dying. They've bought themselves some time. If we had the government of the day say we're going to do this, we could have it implemented and in law and have Australians not be treated like criminals, being able to make this choice. Let's remember that most people who make this choice do it safely, they do it occasionally. They do it because they enjoy it and it brings them pleasure, and they do it without any adverse impacts to their health. That's the reality for the majority of Australia, and that's why nearly seven million Australians have tried it at some stage. We could be there in a year, no problem at all. But what we'd need is a bit of courage from the Labor party or the Liberal Party.

Great, thanks doc. Look forward to talking with you on April 20, 2019.