NSW Premier Chris Minns has backed a proposal that would let medicinal cannabis users drive on a valid prescription, with a three-strikes system that would treat a first positive THC reading as a fine rather than a conviction.
The shift matters now because it would rewrite a basic road rule for thousands of patients in NSW, and it comes as the state is still wrestling with how to balance treatment access against road safety enforcement. The NSW treasurer has already described the idea as common sense.
For people like Teresa Nicoletti, a lawyer with the Australian Medicinal Cannabis Association, the debate is not as simple as drawing a line on a test result. She says there is no accepted amount of THC that will cause impairment, and that problem sits at the centre of the government’s plan.
The wider evidence is bleak. A 2026 review in Current Addiction Reports by Metrik, Bush, Gunn and McCarthy found THC impairs all eight executive function domains critical to safe driving, and said inhaled cannabis can cause measurable driving impairment for four to five hours after use. The same review said 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. It also said cannabis-involved crashes more than doubled between 2000 and 2018.
Other studies point the same way. Research published in the BMJ by Asbridge and colleagues found acute cannabis use nearly doubles crash risk, while separate controlled studies have found significant driving impairment at THC blood concentrations below most existing legal thresholds. That is why the NSW parliament’s 2024 inquiry, which found no scientific consensus on safe THC levels, looms over the government’s proposal even as it moves ahead.
The friction is obvious: NSW is backing a driving change without saying what exact THC threshold or enforcement standard it would use. That leaves police, patients and the courts to guess how a law built around prescription access would work in practice, even as road deaths and serious injuries remain high. In the 12 months to April 2026, 351 people were killed on NSW roads, up 5.1 per cent on the previous year, and in 2025, 11,667 people were hospitalised with serious injuries, up from 11,120 the year before.
For now, Minns has put his weight behind the proposal. What remains unanswered is whether NSW can write a driving law for medicinal cannabis users that is actually enforceable without pretending the science offers a safety line it does not yet have.
