Policy Analysis Paper: Medicinal cannabis and driving: the intersection of health and road safety policy



Recent shifting attitudes towards the medical use of cannabis has seen legal access pathways established in many jurisdictions in North America, Europe and Australasia. However, the positioning of cannabis as a legitimate medical product produces some tensions with other regulatory frameworks. A notable example of this is the so-called ‘zero tolerance’ drug driving legal frameworks, which criminalise the presence of THC (tetrahydrocannabinol) in a driver’s bodily fluids irrespective of impairment. Here we undertake an analysis of this policy issue based on a case study of the introduction of medicinal cannabis in Australia.


We examine the regulatory approaches used for managing road safety risks associated with potentially impairing prescription medicines and illicit drugs in Australian jurisdictions, as well as providing an overview of evidence relating to cannabis and road safety risk, unintended impacts of the ‘zero-tolerance’ approach on patients, and the regulation of medicinal cannabis and driving in comparable jurisdictions.


Road safety risks associated with medicinal cannabis appear similar or lower than numerous other potentially impairing prescription medications. The application of presence-based offences to medicinal cannabis patients appears to derive from the historical status of cannabis as a prohibited drug with no legitimate medical application. This approach is resulting in patient harms including criminal sanctions when not impaired and using the drug as directed by their doctor, or the forfeiting of car use and related mobility. Others who need to drive are excluded from accessing a needed medication and associated therapeutic benefit. ‘Medical exemptions’ for medicinal cannabis in comparable jurisdictions and other drugs included in presence offences in Australia (e.g. methadone) demonstrate a feasible alternative approach.


We conclude that in medical-only access models there is little evidence to justify the differential treatment of medicinal cannabis patients, compared with those taking other prescription medications with potentially impairing effects.

DanielPerkinsabHughBrophyaIain S.McGregorcPaulaO’BriendJuliaQuiltereLukeMcNamarafJeromeSarrisghMarkStevensoniPennyGleesonjJustinSinclairgPaulDietzek

Office of Medicinal Cannabis, Department of Health, Melbourne, VIC 3000, Australia
School of Social and Political Science, University of Melbourne, Parkville, VIC 3010, Australia
The Lambert Initiative for Cannabinoid Therapeutics, Brain and Mind Centre, The University of Sydney, Sydney, NSW 2050, Australia. Faculty of Science, School of Psychology, The University of Sydney, Sydney, NSW 2006, Australia
Melbourne Law School, University of Melbourne, Parkville, VIC 3010, Australia
School of Law, University of Wollongong, Northfields Ave, Wollongong, NSW 2522, Australia
Centre for Crime, Law and Justice, Faculty of Law and Justice, University of New South Wales, Sydney, NSW 2052, Australia
NICM Health Research institute, Western Sydney University, Westmead, NSW 2145, Australia
Professorial Unit, The Melbourne Clinic, Department of Psychiatry, University of Melbourne, Melbourne, 130 Church St, Richmond, VIC 3121, Australia
Urban Transport and Public Health, University of Melbourne, Parkville, VIC 3000, Australia
Deakin Law School, Deakin University, Burwood, VIC 3125, Australia
Behaviours and Health Risks Program, Burnet Institute, Melbourne, VIC 3004, Australia. National Drug Research Institute, Curtin University, Melbourne, VIC 3004, Australia

Available online 6 June 2021.


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