What was supposed to be a major win for medicinal cannabis patients is rapidly turning into a debate about privacy, surveillance and whether the reforms go far enough.

The Minns Government has announced plans to protect medicinal cannabis users from automatically losing their licence after a positive roadside drug test. But the proposed changes come with a catch: drivers would have to register their prescription with the transport department.

The requirement has triggered a backlash from some medicinal cannabis users, who say they do not trust the government to hold a register of patients and fear the information could be misused.

Many are also questioning the government’s proposal to introduce a legal THC saliva limit, arguing there is little evidence that THC levels directly correlate with driver impairment.

The debate is particularly relevant in the Northern Rivers, where drivers can cross into Queensland and find themselves subject to a completely different set of rules.

“No thanks, I won’t be registering onto some weird surveillance list,” wrote one woman on Facebook. “I do not trust NSW police not to use this information to profile me.”

“This is discrimination by our government in favour of allowing pharmaceutical company products go to market totally untested on our roads,” wrote another person.

President of Legalise Cannabis Australia and Nimbin resident Michael Balderstone is aware the prospect of registering is upsetting many.

“As someone said to me today, the police have been hunting me for fifty years, how can I trust them not to target my car when they know I’m on the medical cannabis register,” he wrote in a social media post.

NSW is not the first state to protect ‘medcan’ drivers

New South Wales is neither the first nor only Australian state to protect medicinal cannabis users from loss of licence.

The proposed NSW medicinal cannabis driving laws are complex and inconsistent with the safeguards offered to medicinal cannabis script-holders in Victoria and Tasmania.

Tasmania

In Tasmania, you can drive if prescribed medicinal cannabis by a Tasmanian doctor, provided you are not impaired.

There is a defence in Section 6A(2) of the Road Safety (Alcohol and Drugs) Act 1970: “A person does not commit an offence against subsection (1) if the prescribed illicit drug was obtained and administered in accordance with the Poisons Act 1971 …”

That means you can drive with your prescription if you are not under the influence of cannabis. If you fail a roadside drug test, you have a legal defence. The onus is on police to show you were impaired.

The Tasmanian Government has not mandated a limit of less than 50 ng/mL of THC in your saliva, and you don’t have to register your prescription.

Victoria

It’s a similar situation in Victoria, though the Allan Government is awaiting the outcome of a closed-circuit medicinal cannabis driving trial led by Swinburne University of Technology.

There is a possibility it will amend the laws once those results are in.

Technically, it’s still illegal to drive with THC in your system, but since 2025, if you fail a roadside drug test, have a prescription and were unimpaired, you can go to court.

Victorian magistrates now have the power to let you keep your licence and keep driving.

There is no legislated “safe” THC level in Victoria, and you don’t have to register your prescription.

New South Wales

Already in NSW, a driver who has failed a roadside drug test can appear before the court, explain their circumstances and appeal for a Section 10.

A Section 10 dismissal, under the Crimes (Sentencing Procedure) Act 1999, is when the judge finds you guilty, but you do not receive a criminal record or licence disqualification.

But it is up to the judge whether they issue a Section 10.

The proposed NSW cannabis driving reforms will deliver more security to medicinal cannabis patients, so a big congratulations to MP Jeremy Buckingham of Legalise Cannabis NSW for campaigning hard to change the law.

However, the reforms are by no means perfect.

Should there be a legal cannabis/THC driving limit?

Mr Balderstone is also sceptical about the THC limit.

“50 ng is not much … fifty parts of one billion! I registered 1200ng about two hours after smoking a joint,” he wrote on Facebook.

Research has found a weak or inconsistent connection between THC in saliva and the degree of driver impairment.

That means some cannabis users can be impaired by low levels of THC, while others will show few signs of being affected by high THC levels.

Cannabis does not behave like alcohol. Its effects cannot be easily measured.

In 2021, researchers at the University of Sydney analysed past studies on driving performance and THC in blood and saliva.

The researchers found that fluid THC concentrations are relatively poor or inconsistent indicators of cannabis-induced impairment.

Despite these findings, the Minns Government is settling on a THC limit.

In Europe, about 20 countries have set low limits for THC in drivers’ saliva. This includes France, Germany, Denmark and Italy.

So have five US states: Colorado, Nevada, Ohio, Pennsylvania and Washington.

California, the first US state to introduce medicinal cannabis, has not set a THC limit for driving.

Why? Because a panel of experts led by the California Highway Patrol concluded THC metabolites do not correlate with driver impairment.

In California, if an officer suspects you are driving impaired, you will be asked to do a sobriety test that includes walk-and-turns and horizontal gaze eye movements.

There are 1700 specialists in the California police force who are certified Drug Recognition Evaluators.

If you are arrested for suspicion of a cannabis DUI, police can then go to a judge and demand a blood test.

Australia’s cannabis driving laws are a patchwork

So in Australia, there is now a dis-‘joint’ (excuse the pun) in how medicinal cannabis drivers are treated.

Western Australia, South Australia, Queensland, the Northern Territory and the ACT continue to take a largely zero-tolerance approach to THC and driving.

New South Wales is moving towards a European-style model that includes a THC saliva threshold and a prescription register.

Meanwhile, Victoria and Tasmania have adopted a different approach, allowing medicinal cannabis patients to rely on a legal defence if they hold a valid prescription and are not impaired.

For patients living in border regions such as the Northern Rivers, that means the legality of driving can change simply by crossing a state border.

Does this make any sense? Have Australia’s drug laws ever made sense?

We still criminalise recreational cannabis, but a drug like alcohol is widely used, sold and advertised … but that’s another conversation.

Christine Tondorf was previously a parliamentary advisor to Legalise Cannabis Victoria. She has a Bachelor of Arts, majoring in criminology, from the University of Melbourne and a Master of Arts, majoring in media and humanities, from Southern Cross University. The opinions in this piece are her own.