Dr John Crozier’s Opinion Piece on Medicinal Cannabis & Driving Gets It Wrong

In today’s SMH there is an appalling opinion column headlined “As a trauma surgeon, I know cannabis kills. Don’t green-light medicinal drivers” by surgeon John Crozier.

It is so full of downright inaccuracies, that I am surprised it got a run. It typifies the response of the naysayers to this important reform, and cannot go unchallenged.

Here are the highlights.

“So when a government announces it is prepared to make it easier for impaired drivers to be on the roads where these patients come from, I am not going to use diplomatic language. I am going to say what this is: a failure of political courage that will cost lives”.

Wrong on every count. The government is not making it easier for impaired drivers to be on the road. That is the whole concept – it is making it easier for unimpaired drivers. If you are impaired, there is a different offence, remaining on the books. Not just that, but the alternative is that patients are using their prescription medications, which are not policed at detectable levels. This will not cost lives. In Tasmania, which has had a defence for many years, there is not one iota of evidence that their road trauma has increased as a result. This will save lives, not cost them, as people have clear levels they must be under, moderate their intake to suit, and have an opportunity to reduce with medical advice.

“NSW Premier Chris Minns has thrown his support behind a proposal allowing “medicinal” cannabis users to drive on a valid prescription, with a “three strikes” system that merely fines – rather than convicts – a driver who returns a positive THC reading on their first offence”.

Sometimes doctors should not try to be lawyers. First, there is no fine only for a first offence – there is a suspension, and it is recorded on your traffic record. If you go to court, it is a conviction. If you take the automatic suspension, you are off the road for three months. There has never been a “fine only” system in NSW, and there will not be under this proposal. Not even a court can fine only. (Perhaps if there was a fine only option it would be fairer). Second, this is not first offence dependant.  

“Inhaled cannabis causes measurable driving impairment for four to five hours after inhalation”. 

Yes, there is some evidence for that. This proposal recognises this by imposing a level most likely to be not reached following that time period. The proposal, arguably too conservatively, sets a level that accounts for this exact research. This is an argument for the proposal, not against it.

”cannabis is now the No. 1 substance found in the blood of seriously or fatally injured road users in American states that have liberalised its use – appearing in 25.1 per cent of cases, ahead of alcohol at 23.1 per cent. Cannabis-involved crashes more than doubled between 2000 and 2018”. 

Yes, cannabis is found in the blood of road users suffering injury or death. But there is a difference between correlation and causation. First, in most of those cases traces of cannabis are found along with other legal and illegal drugs. Second, there is no evidence that any of that trauma was caused by the traces of cannabis, let alone that they were prescribed medicinal cannabis patients consuming in accordance with their prescriptions. They are not “cannabis-involved” crashes in the sense that cannabis was the cause.  Third, given that most fatalities worldwide are males from 18 to 25, and their cannabis use is significantly higher than other groups, it is unsurprising that traces of THC are found in their blood. There has not been a single coronial finding, anywhere in the world, that a medicinal cannabis consumer, using in accordance with their prescription, has caused a death as a result of that consumption. That is strong evidence of a lack of harm given there have been over a million prescriptions in Australia alone.

“Research published in the BMJ by Asbridge and colleagues found acute cannabis use nearly doubles crash risk. Separate controlled studies found significant driving impairment at THC blood concentrations below most existing legal thresholds”.

The fist sentence is stating the bleedingly obvious with “acute” being the operative word. Don’t drive impaired. Everyone agrees with that. The second statement misunderstands the law again. There is no legal threshold in NSW currently. It is an offence to drive with any THC in your system – period. Perhaps the author is referring to international studies – however, medicinal cannabis users are going to be bound by a very conservative 50ng in NSW. The truth is that all drugs affect people differently, and unless we are going to make zero detections for alcohol, all prescription drugs, all illicit drugs and THC, then we have to do our best with the information we have. To continue to punish unimpaired medicinal cannabis users alone is grossly unjust.

On this, I often use myself as an example. I do not drink, but if I had a glass of wine I would not be fit to drive, but still be under the limit.

And let’s not forget the Tasmanian experience, and the effect of going back to pharmaceuticals. Or driving in pain and lacking sleep.

“While this political debate proceeds, people are dying on NSW roads at an accelerating rate”. 

Yep, that is true. But that is in an environment where there are 200,00 random tests for drugs in NSW, and Australia does more random THC testing than the rest of the world combined. It is a failed policy, and police would be better off devoting resources to proven road safety measures. Where is the evidence this has saved lives? Meanwhile, thousands of medicinal cannabis users are punished for nothing.

Tasmania’s road toll has been going down since 2023. Time for a shift in policy.

“And into this environment, the NSW government is preparing to tell cannabis users that driving after medicating is acceptable, provided they have a piece of paper from a doctor”.

Incorrect again. First, they must register. Then they must do a course. Then they must be under 50ng. And of course, they must not be impaired, or else they can be charged with a more serious offence anyway. To suggest that a prescription alone makes drug detectable driving permissible is misreading the legislative proposal comprehensively.

“Under this proposal, presence on a first offence attracts nothing more than a fine. That is not a deterrent. That is a licence fee”.

Again, it is surprising that this was able to be published. It is simply incorrect on current law and proposed law. There is no “fine only” model anywhere in discussion. 

The truth is that we all want to end suffering. This proposal will. If I believed for one moment that this would increase the road toll, I would be opposing it too. So would the Police Association. So would the legal fraternity, who have much to lose in legal fees. I am unhappy with many aspects of the proposal – but I am willing to park those reservations in refuting this article.

Painting the proposal inaccurately will do nothing to further this debate.

Professor David Heilpern

Dean of Law and Chair of Discipline

Faculty of Business, Law and Arts

Drive Change Team