Current NSW law, the 2026 reform proposal and practical steps after a roadside test.

Key point: A lawful prescription for a THC-containing cannabis medicine does not currently give a driver permission to drive with THC present in their system in NSW. A reform Bill was introduced in June 2026, but it is not yet law.

Medicinal cannabis is now a legitimate treatment option for many Australians. For patients in New South Wales, however, the road rules remain difficult: the criminal law generally focuses on the presence of THC, not simply whether the driver appeared impaired.

That distinction matters. A patient may feel capable of driving, may have taken medication exactly as prescribed and may not have consumed it immediately before driving. Even so, a positive roadside drug test can still lead to a drug-driving allegation under the law that applies today.

This guide explains the current NSW position, the reform proposed in 2026 and the practical steps a patient should take after a roadside test. It is general information, not advice about a particular case.

The Law That Applies Now

Section 111 of the Road Transport Act 2013 (NSW) makes it an offence to drive, attempt to drive or occupy the driver’s seat and attempt to put a motor vehicle in motion while a prescribed illicit drug is present in the person’s oral fluid, blood or urine. Delta-9-tetrahydrocannabinol (usually called THC) is one of the prescribed illicit drugs.

For this offence, the prosecution does not ordinarily need to prove that the person’s driving was affected. The central issues are usually whether the person drove or attempted to drive and whether an authorised analysis detected a prescribed illicit drug in the relevant sample.

This is different from driving under the influence. An allegation of driving under the influence concerns the person’s condition and capacity to drive. A presence offence under section 111 can be alleged even where there was no erratic driving and no obvious sign of impairment.

Does a Prescription Provide a Defence?

Under the current NSW presence offence, a prescription for a THC-containing cannabis medicine is not, by itself, a defence. The NSW Government’s medicinal cannabis guidance says it is illegal for patients taking cannabis medicines containing THC to drive.

The position is different for a cannabidiol-only medicine. CBD is not one of the prescribed illicit drugs for roadside drug-testing purposes. A person taking a CBD-only medicine may lawfully drive, provided the medicine has not impaired their ability to drive. Patients should check their medicine’s contents and discuss its effects with their treating practitioner.

Labels such as “medicinal cannabis” or “CBD product” are not enough. A patient should confirm whether the medicine contains THC and follow the prescriber’s directions and warnings.

What Happens During Roadside Drug Testing?

Police may require an eligible driver to undergo an oral-fluid test. If the first test is positive, police may conduct a further test and arrange laboratory analysis of a sample. Police can also prohibit the person from driving for a period following the roadside process.

An initial roadside result is not necessarily the final evidence used in court. Laboratory confirmation, the continuity and handling of the sample, compliance with statutory procedures and the admissibility of evidence may all require consideration in an individual case.

Drivers should remain calm, comply with lawful directions and avoid arguing their case at the roadside. They should not provide a false explanation. There is a distinction between complying with testing requirements and volunteering a detailed account that may later be used as evidence. Legal advice should be obtained promptly.

Current Penalties for a Presence Offence

Penalty amounts and licence consequences depend on the person’s record and how the matter is dealt with.

Penalties are subject to change. “Automatic” is the period that applies unless the court orders a different period within its statutory powers. The outcome of any case depends on the charge, record, evidence and sentencing material.

Where a person receives a penalty notice, Transport for NSW may issue a suspension notice. Check the available options and deadlines immediately. Electing to have a court determine a penalty notice carries risk: the court may impose a different outcome, and costs or conviction consequences may arise. Do not treat it as a routine way to get a shorter suspension.

The 2026 Proposed Reform

On 25 June 2026, the NSW Government introduced the Road Transport Legislation Amendment (Medical Cannabis and Driving Offences) Bill 2026. The proposal would create a tightly controlled pathway for certain patients prescribed THC-containing medicinal cannabis.

As at August 2026, the Bill remains before the NSW Parliament. It has not commenced and does not change what drivers must do today.

Under the proposal announced by the Government:

1. Eligible patients would first register with Transport for NSW, hold a valid prescription and complete online education
2. The scheme would be limited to holders of an unrestricted NSW driver licence
3. Learner, provisional and commercial drivers would be excluded
4. A positive roadside test would still result in a 24-hour driving prohibition and laboratory analysis
5. Where the laboratory result was below 50 nanograms of THC per millilitre, no further action would be taken
6. At or above that threshold, the first and second detections within two years would attract warnings
7. A third detection within two years would attract a $704 fine and a minimum three-month suspension
8. Ordinary penalties would continue to apply where alcohol or other illicit drugs were also detected
9. Police could still prosecute impairment-based offences, and the serious-crash testing regime would remain

These features may change as the Bill proceeds through Parliament. Patients should rely on the law in force, not assume that an announced reform already applies.

Why Elapsed Time Is Not a Simple Answer

People often ask how many hours they must wait after taking medicinal cannabis. No single waiting period guarantees a negative roadside result for every person and product.

Detection can be affected by the medicine, dose, method of administration, frequency of use and individual metabolism. A prescriber’s instruction about impairment or safe use is important medical guidance, but it cannot guarantee that THC will not be detected under the current legal test.

The safest legal approach while the present law remains in force is not to drive after taking a THC-containing cannabis medicine. Patients who depend on driving should discuss treatment options and transport planning with their prescriber. They should not stop or alter prescribed treatment without medical advice.

What to Do After a Positive Test or Charge

1. Comply with the driving prohibition. Do not drive while prohibited or suspended. A further offence can substantially worsen the position.
2. Keep every document. Retain the police notice, court attendance notice, Transport for NSW correspondence, laboratory result and envelope showing when any notice arrived.
3. Record the timeline privately. Note the date and time of the test, what police said, the testing steps, the last prescribed dose and any witnesses. Do this while events are fresh, but do not publish the account online.
4. Collect prescription records. Keep the current prescription, dispensing history, product label and treating practitioner’s contact details. These do not automatically answer liability, but may be relevant to advice and sentencing.
5. Check every deadline. Court dates, licence-suspension dates and election periods are strict. Missing one may remove an option.
6. Obtain advice before electing court. A lawyer can explain the evidence, available pleas, risks, possible orders and what material would assist.

What a Lawyer Will Examine

1. The precise offence and whether the prosecution can prove each element
2. The testing certificates and statutory presumptions
3. Whether police complied with relevant testing and evidentiary procedures
4. The continuity and admissibility of the sample and analysis
5. Any properly available statutory or common-law issue
6. The person’s driving and criminal history
7. Whether an order without conviction is realistically available if there is a plea or finding of guilt
8. The evidence needed to explain the prescription, personal circumstances and risk of reoffending

A prescription is important context, but advice should not assume it automatically defeats the current presence offence.

Frequently Asked Questions

Charged After a Roadside Drug Test in NSW?

The gap between lawful medical treatment and NSW’s presence-based driving law is real. Reform is now before Parliament, but the existing offence continues to apply unless and until new legislation commences.

If you have been charged with a drug driving offence after taking prescribed medicinal cannabis, the most important step is to get legal advice promptly. The evidence, the testing process and the specific charge all matter, and deadlines for elections and responses are strict.

At Rezae & Co Lawyers, we advise clients on drug driving allegations, licence consequences and police powers across Parramatta, Sydney and NSW.

Call Rezae & Co Lawyers on 02 8893 1217 for a free 30-minute consultation.