Drug driving is one of the most common charges in the Magistrates’ Court, and a positive roadside saliva test does not automatically mean the case is hopeless. McMahon Criminal Defence Lawyers defends drug driving charges at the Ballarat Magistrates’ Court and across Victoria on fixed fees.

The Offences

Drug driving offences sit in section 49 of the Road Safety Act 1986. The most common are:

• Driving with a prescribed illicit drug present — the three prescribed illicit drugs are THC (cannabis), methylamphetamine (ice) and MDMA (ecstasy). Any detectable trace is enough. Unlike drink driving, there is no permitted limit.
• Detection in an oral fluid sample taken within three hours of driving or being in charge of a motor vehicle.
• Driving while impaired by a drug — a more serious charge, usually following a drug impairment assessment at a police station.
• Refusing a test or sample — refusing a preliminary oral fluid test, a drug assessment, or a blood or urine sample. Refusal is treated far more seriously than the underlying charge.
• Drugs and alcohol together, which carries its own penalties.

Penalties and Licence Loss

For most people the licence consequences matter more than the fine. As a general guide for a first offence:

• Illicit drug present: a fine, and a minimum licence cancellation of 6 months.
• Driving while impaired: a higher fine, and a minimum of 12 months.
• Refusing a test or sample: the most serious, with a minimum of 2 years and the real prospect of a more severe sentence.

Second and subsequent offences attract substantially higher fines and longer disqualification periods. A conviction also affects work licences, heavy vehicle and passenger vehicle accreditation, and travel to some countries. Whether a conviction is recorded is often the most important issue in the case.

Getting Your Licence Back

The disqualification is not the end of it. Anyone found guilty of a drug driving offence, or a combined drink and drug driving offence, must apply to the court for a licence eligibility order once the minimum period has been served. VicRoads will not reissue the licence without it.

You must also complete a behaviour change program with a VicRoads-approved agency. The standard program is a single counselling session, but an intensive program of group sessions plus counselling applies to people with prior drink or drug driving convictions, to refusal offences, and to serious drug driving offences. VicRoads writes to you about which program applies.

One distinction matters here. Where the matter is dealt with by an infringement notice, the licence is suspended rather than cancelled, and no licence eligibility order is needed. Where you are charged and found guilty in court, the licence is cancelled and the full process applies. We can advise which path your matter is on.

Medicinal Cannabis and Driving

From 1 March 2025, the law changed for drivers with a valid medicinal cannabis prescription. Where THC is detected, a magistrate now has a discretion about licence cancellation, rather than being obliged to impose it, and will consider matters such as the prescription and any evidence of impairment.

Two points are commonly misunderstood. Driving with any THC in your system remains an offence, even on a lawful prescription; and the change does not affect the separate offence of driving while impaired. If you hold a prescription, bring it, along with your prescribing doctor’s details, to your first appointment.

Defending the Charge

• Procedural failures — the testing and sampling provisions are detailed, and police must comply with them;
• Analysis and chain of custody — the reliability of the sample and the certificate relied on by the prosecution;
• Whether you were driving or in charge of the vehicle at the relevant time;
• Reasonable excuse, in refusal cases, including medical reasons for an inability to provide a sample;
• Medicinal cannabis, where a prescription is held; and
• Careful preparation of a plea to keep the disqualification to the statutory minimum and to argue against a conviction being recorded, including diversion in suitable cases.

Related charges are often laid at the same time, including drug possession or trafficking, drink driving and other traffic offences. In the most serious cases, drug driving arises alongside culpable or dangerous driving causing death.

If you have been charged, do not simply plead guilty by post. Contact us for advice before your court date.

Frequently Asked Questions

Will I lose my licence for a first drug driving offence?

If the charge is proved, a minimum period of licence cancellation applies, generally 6 months for a first offence involving a prescribed illicit drug. Longer minimums apply to impaired driving and to refusing a test. The court has no power to go below the statutory minimum, which is why the real work is in examining whether the charge can be defended and in how the plea is prepared.

I have a medicinal cannabis prescription. Is it still an offence?

Yes. Driving with any THC in your system remains an offence, even with a valid prescription. Since 1 March 2025, however, a magistrate has a discretion about whether to cancel your licence, taking into account the prescription and any evidence of impairment. Bring your prescription and your doctor’s details to your appointment.

How long does cannabis stay detectable in a saliva test?

It varies considerably with the amount used, how it was taken and the individual. THC can be detected well after any effect has worn off, which is why people are often charged when they do not feel affected. Being unaffected is not a defence to the charge of having a drug present, though it can be relevant to sentencing and to medicinal cannabis cases.

Can I get diversion for drug driving?

Diversion is generally not available for offences that carry a mandatory licence cancellation, which covers most drug driving charges. It may be available for some related summary charges. We will tell you honestly whether diversion is realistic in your case.

What happens if I refuse a roadside saliva test?

Refusing is treated much more seriously than testing positive. The minimum disqualification is substantially longer, the maximum fine is much higher, and imprisonment is possible for repeat offending. A reasonable excuse, such as a medical inability to provide a sample, may be a defence, and these cases turn on the detail of what police said and did.

Do I have to go to court?

Yes, drug driving charges are dealt with in the Magistrates’ Court. We appear for you at the Ballarat Magistrates’ Court and at courts across the region, including Ararat, Bacchus Marsh and Colac.

Get Expert Legal Advice — Fixed Fees, No Surprises

McMahon Criminal Defence Lawyers provides experienced, fixed-fee representation for this charge and all criminal matters, appearing at the Ballarat Magistrates’ Court and across Victoria. Contact us for a free, confidential initial consultation.

Get in Touch

Contact us today for a confidential consultation with an experienced criminal defence lawyer.