Drug driving and the law 

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This information is general and should not be relied upon as a substitute for legal advice. The Legal Services Commission provides free advice for most legal problems. Contact the Legal Helpline on 1300 366 424 or visit www.lsc.sa.gov.au or www.lawhandbook.sa.gov.au

It is a criminal offence to drive, or attempt to drive, a motor vehicle while a prescribed drug is present in your system. Roadside drug screening (saliva) tests can detect THC (cannabis), methylamphetamine (speed, ice, or crystal meth) and MDMA (ecstasy).

Unlike drink driving, there is no minimum amount of drug that has to be present in your system for you to be guilty of an offence. Many drugs can remain in your system for hours or even days after they have been taken.

Drug testing

Any uniformed police officer can require a driver to undergo a random roadside drug screening (saliva) test, so long as an alcotest or breath analysis test has first been conducted. If the saliva test indicates a positive reading for the presence of drugs, an oral fluid sample will be taken and sent for laboratory testing.

If the presence of drugs is confirmed by laboratory testing, you will be charged with driving with a 'prescribed drug in oral fluid or blood' or driving under the influence (DUI). This process can take several weeks. Police may issue you with an on-the-spot licence disqualification if they reasonably believe you have committed the offence.

What is a vehicle?

You can only commit the offence of driving with a prescribed drug in oral fluid or blood when you drive or attempt to drive a motor vehicle. This includes cars, trucks, motor bikes and even includes e-scooters and other electric personal transporters. 

Driving under the influence applies even more broadly to driving or attempting to drive a vehicle, which, in addition to motor vehicles, includes trams, bicycles, animals, animal-drawn vehicles and motorised wheelchairs that can travel over 10 kilometres per hour.      

What about other drugs?

Drug screening testing is only currently used for the detection of THC, methylamphetamine and MDMA. However, drivers impaired by other drugs (whether prescription or illicit) may be charged with driving under the influence of drugs.

Can I refuse a drug test?

If you have already submitted to an alcotest or breath analysis, the police may also require you to submit to a drug test. It is an offence to refuse a request for a drug screening test, oral fluid analysis or blood test. The penalties that apply if you refuse to cooperate are more serious than those for a first offence of drug driving itself. 

On-the-spot disqualifications

Police may issue an on-the-spot disqualification notice for the offences of drug driving, refuse drug screening or oral analysis test, or refuse blood test. This disqualification will usually be for the minimum period for the charge you are likely to face. A summons will be sent at a later date for you to appear in court to determine the actual penalty, including the length of the disqualification and fine. When you are sentenced, the court can backdate the disqualification period to start on the day you were first disqualified.

For a first offence of drug driving or drug driving while child aged under 16 is present, you will usually receive an expiation notice after the forensic laboratory results have confirmed the presence of drugs in your system. For these offences, if the expiation notice is paid then no summons will be sent to you and you do not have to go to court, but you will still be required to serve the 3-month licence disqualification. You may receive a separate notification about your licence disqualification.

Can I keep driving?

If you test positive for THC, methylamphetamine or MDMA on a drug screening test but the police do not issue you with an on-the-spot disqualification notice, they may ask you to stop driving until the drug is no longer detectable in your system. For THC this will usually be up to 4 hours and for methylamphetamine and MDMA 24 hours. The police can direct you to leave your vehicle and surrender your keys. Ask the police for help to arrange alternative transport if necessary. If you attempt to drive away, you may be arrested.

Can I be blood tested?

Anyone 10 years or older who is admitted to hospital for treatment following a road accident must be blood tested. The blood test must be done as soon as possible after you are admitted to hospital and within 8 hours of a motor vehicle accident.  The sample is sent to the police for analysis.

If you were the driver and the result indicates that you had a prescribed drug present in your blood then you will be charged. If you refuse a blood test without good medical reason you can be fined and may receive more serious penalties, including disqualification, if you were the driver of the vehicle.

Driving under the influence (DUI)

It is an offence to drive, or attempt to drive, a vehicle while so much under the influence of a drug as to be incapable of exercising effective control of the vehicle.

You are deemed to be incapable of exercising effective control of a vehicle if your physical or mental capabilities are appreciably impaired. Police may use their observations to show that you could not exercise effective control. A test showing the presence of a drug in your system may form part of this evidence but is not essential. This offence is separate to Drug Driving and you cannot be convicted of both in relation to the same incident.

Penalties

If you are convicted of a drug driving offence the court must impose at least the minimum disqualification period, but can impose a longer period. A fine and demerit points will also apply. The following penalties are for first offences only:

*The police normally issue an expiation notice for these offences. Even if the expiation notice is paid, a 3-month licence disqualification applies. If the case goes to court, the court must impose a minimum disqualification of 6 months.

Higher penalties apply if you have previous convictions for drug driving. Probationary, provisional and learner drivers face penalties for a breach of licence conditions in addition to drug driving penalties. 

Can I keep my licence?

If you are guilty of a drug driving offence then the court has very limited powers to reduce the penalties below the minimum, including the period of disqualification. Personal hardship or loss of employment are not grounds to keep your licence. You cannot get a restricted licence or a licence just for work purposes - the disqualification is total. A court may reduce a disqualification period in limited circumstances where the offence is considered trifling. It is recommended you seek legal advice before making any trifling application in court.

After disqualification 

When you are disqualified from driving, your licence is cancelled. This means that when you have served your full disqualification period, you must apply to renew your licence before driving again. It is an offence to drive while your licence is disqualified or to drive after your disqualification period has ended if you have not renewed your licence. These offences are treated seriously by the courts and can result in imprisonment. Seek legal advice if you have been charged with either of these offences. 

Following disqualification, you must hold a probationary licence for at least 12 months. As a probationary licence holder you must carry your licence at all times while driving. Breach of the conditions or incursion of 2 or more demerit points can result in further disqualification. 

Drug dependency assessment

If you are convicted of a drug driving offence where a child aged under 16 was also present in the vehicle, or you have other previous convictions for prescribed drug driving offences committed within the past 5 years, you will be required to show you are not dependent on drugs before your licence is reissued. This will involve undergoing a drug dependency assessment to determine whether you are dependent on drugs. You are required to pay for the cost of the assessment and any treatment program.

Demerit point disqualification

If you are guilty of a drug driving offence, you will incur demerit points as part of the penalty. Depending on the number of demerit points you had prior to the drug driving offence, you may have to serve another disqualification period because you have incurred too many points. If you are on a full licence and incur 12 or more demerit points you will receive a notice from the Registrar of Motor Vehicles disqualifying you for at least 3 months. With this disqualification, you can elect to abide by a 'good behaviour' condition which enables you to retain your licence. However, if this is breached you will need to serve double the original disqualification.

What if I had an accident?

If you have an accident while under the influence of drugs you may also face other traffic offences. These can range from driving without due care to causing death or harm by dangerous driving. In addition, your insurance policy may be affected if it can be shown that you were under the influence at the time of the accident.

If someone is injured due to your negligent driving when you are under the influence, your insurer may sue you to recover compensation paid to third parties. Even if you are injured and the accident was mostly the fault of another driver, your compensation may be reduced. As issues with insurance and liability can be complicated it is best to seek legal advice.

Do I need a lawyer?

If you are pleading guilty to a drug driving offence you can represent yourself if you choose. Even if you are representing yourself you should seek legal advice before going to court. Legal aid will only be granted if there is a likelihood of imprisonment and this is not usually the case for drug driving charges. You may be eligible for legal aid if you have been charged with DUI and have prior convictions, if you have been charged with driving while disqualified, or if your case is particularly serious. 

If you are representing yourself, you will need to tell the court about what happened at the time of the offence, such as why you drove whilst you were under the influence of drugs, what you will do to ensure that you do not use drugs and drive again, and some details about your personal circumstances, such as your work, family and financial situation.

Call the Legal Helpline on 1300 366 424 for advice or to make an appointment for free legal advice at the Legal Services Commission.

6 November 2023