I have a major beef with this mealy-mouthed suggestion from the Chief Science Advisor's panel that it’s still uncertain whether legalising dope increases harm.

We already have an addiction-fueled mental health crisis in this country, much of which can be sheeted home to recreational cannabis abuse and psychosis. Why risk aggravating that problem even more, by normalising and legitimising dope, by surrendering on the law? There are so many unintended consequences, which I don’t believe this panel has fully considered.

Let me give you an example of the elevated threat of real harm to you and me. Drug-driving.

Last week the Road Transport Forum made their views very clear about the higher risks on our roads if recreational cannabis use is legalised. It raises the stakes on risk.

And bear in mind, the number of people being killed by drug impaired drivers on our roads is already higher than those killed by drivers above the legal alcohol limit. Do we want to ratchet that up?

Here's some stats from various North American jurisdictions that legalised dope.

Post-legalisation in Colorado, cannabis-related roads deaths increased 151%. In Washington State, they doubled. A quarter of Canadians aged 18-34 who smoke dope admit to driving after consuming, or have been a passenger with someone who just has. Idiots.

In a 2018 Colorado State study, 27% of cannabis users admitted to driving high almost daily. And a New Zealand health study found that habitual users of cannabis have about 10 times the risk of causing a road injury or death compared to infrequent or non-users.

Ding ding. I hear alarm bells.

If that's not harm and increased harm, you can call me Hamish.

• PM's chief science adviser: Legal cannabis could reduce harm, but many unknowns

As to the Chief Science Advisor's Panel, and this cop-out conclusion that it’s too early to say whether legalisation leads to increased harm, I have a word of advice. If in doubt, leave it out.

Why subject the nation to this experiment?

It’s just another reason why I believe September’s referendum is destined to crash and burn.