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Drug driving

Roadside drug screening tests

Since 1 July 2006, police have had the power to conduct random roadside drug screening tests to detect drivers under the influence of certain illicit drugs.

Testing is for:

  1. THC (the active substance in cannabis)
  2. methylamphetamine (also known as speed, ice or crystal meth)
  3. MDMA (more commonly known as ecstasy)

Driving with prescribed drug

It is an offence for a person to drive with these drugs in his or her oral fluid or blood — this includes a passenger acting as ‘qualified supervising driver’ for a learner driver. For details of penalties see Alcohol and drug penalties.

Any driver (or qualified supervising driver) may be required to undergo a random roadside drug screening test and tests can be conducted anywhere in South Australia.

Driving with prescribed drug where child aged under 16 present in vehicle

It is an offence for a person to drive with a prescribed drug in their oral fluid or blood, and while a child aged under 16 years is present in the vehicle [see Road Traffic Act 1961 (SA) s 47BA(1a)].

The same penalties for this offence apply as if the person had been charged with driving with a prescribed drug in oral fluid or blood pursuant to section 47BA(1) of the Road Traffic Act 1961 (SA).

A person convicted of the offence of driving with a prescribed drug in oral fluid or blood will be required to undergo a drug dependency assessment prior to having their licence reissued at the end of the disqualification period [see Motor Vehicles Act 1959 (SA) s 79B(2)(c)(i)].

Driving under the influence (DUI)

It is an offence for a person to drive while so much under the influence of a drug as to be incapable of exercising effective control of the vehicle [Road Traffic Act 1961 (SA) s 47(1)]. For the purpose of this offence, you may be deemed to be incapable of exercising effective control if your physical and/or mental capabilities are appreciably impaired. Laboratory testing showing the presence of a drug in your system may form part of the evidence for this offence, but it is not essential.

Driving under the influence (DUI) while child aged under 16 present in vehicle

It is an offence for a person to drive while so much under the influence of a drug as to be incapable of exercising effective control of the vehicle, and while a child aged under 16 years is present in the vehicle [Road Traffic Act 1961 (SA) s 47(1a)].

The same penalties apply as if a person had been charged with driving under the influence pursuant to section 47(1) of the Road Traffic Act 1961 (SA).

A person convicted of this offence will be required to undergo a drug dependency assessment prior to having their licence reissued at the end of the disqualification period [Motor Vehicles Act 1959 (SA) s 79B(2)(c)(i)].

Is there a minimum amount of drugs that can be present without an offence being committed?

Unlike drink driving, where a prescribed concentration of alcohol must be present for an offence to have been committed, the presence of any amount of the drugs tested will constitute an offence of driving with prescribed drug in your oral fluid or blood. THC remains detectable for several hours after the drug has been taken and methylamphetamine and MDMA for a period of 24 hours, or longer, depending on the person.

Can I refuse a drug test?

Where a person has been required to submit to an alcotest or breath analysis [Road Traffic Act 1961 (SA) s 47E], they may also be required to submit to a drug screening test or oral fluid analysis [Road Traffic Act 1961 (SA) ss 47EAA(1) and (2)]. It is an offence to refuse, or to fail to comply with, a request for a drug screening test, oral fluid analysis or blood test. It is also an offence to refuse, or fail to comply with, a request for a drug screening test, oral fluid analysis or blood test where a child aged under 16 years is present in the vehicle [see Road Traffic Act 1961 (SA) s 47EAA(9a)]. For details of penalties see Alcohol and drug penalties.

What happens with the samples taken?

All samples taken must be destroyed if there is no prosecution of any offence or at the conclusion of court proceedings. Samples taken cannot be used in DNA testing nor can they be used in relation to offences other than driving offences.

Can random saliva testing be used to detect other drugs?

Random saliva testing (drug screening testing) will only be used for the detection of THC, methylamphetamine and MDMA. However, drivers impaired by other drugs (whether prescription or illicit) can expect to be charged with the existing offence of driving under the influence of alcohol or drugs.

Who can conduct drug screening tests?

All uniformed police officers can conduct drug screening tests.

How will random drug screening tests be conducted?

On being stopped by police, drivers will first be required to complete an alcohol test.

Drivers may then be requested to provide a saliva sample by placing a swab in their mouth or touching it with their tongue until a sample is collected. This is referred to as a drug screening test.

The initial saliva test can be conducted at the roadside without a driver having to leave his/her vehicle. The sample will be screened at this stage with results being available in approximately 5 minutes.

Where a positive result is recorded from the initial drug screening test, an oral fluid sample will then be collected and sent to Forensic SA for further laboratory analysis.

When will action be taken?

In the event a driver records positive results to drug testing no further action can be taken until the results of the laboratory analysis are known. Before any expiation notice can be issued or charge can be laid the presence of either THC or methylamphetamine must be confirmed by the laboratory analysis. This process will take several weeks but where the presence of these drugs is established the driver will then be fined or charged accordingly.

Can I continue to drive if I have tested positive in a drug screening test?

A driver who tests positive for THC, methylamphetamine or MDMA through an initial drug screening test will be advised by police not to drive until the drug is no longer detectable in their system. For THC this will be up to 4 hours and for methylamphetamine and MDMA 24 hours.

Where a police officer believes a driver to be unfit to drive due to alcohol or drug consumption they have the power to require the driver to surrender their keys and immoblise the vehicle [see Road Traffic Act 1961 (SA) s 40K(4)].

What happens if I receive an expiation notice?

For a first offence of driving with prescribed drug in oral fluid or blood, and after the presence of the drug in oral fluid or blood has been confirmed by laboratory analysis, you will receive an expiation notice. You have the ability to either pay the expiation notice, seek a review of the expiation notice, or elect to be prosecuted, see: Expiation Fees and Fines.

If you pay the expiation notice, you will then receive notification from the Registrar of Motor Vehicles that you will be disqualified for a period of 3 months [see section 139BD of the Motor Vehicles Act 1959 (SA) for the process of service and commencement of notices of disqualification].

If you elect to be prosecuted instead of paying the expiation notice, the potential court ordered disqualification period increases to 6 months [Road Traffic Act 1961 (SA) s 47BA(4)(a)(Ii)].

How will I know I am disqualified?

The disqualification notice is served in the first instance by ordinary post to your last known address. Once received you are required to attend personally at the Department for Planning, Transport and Infrastructure to acknowledge receipt of the notice and pay the Registrar an administration fee.

What will happen if I don’t get the notice or fail to respond to it?

If you fail to comply with the notice another notice will be issued personally by a process server, the cost of which will be met by you.

If personal service is unsuccessful you will be prohibited from transactions with the Department for Planning, Transport and Infrastructure until you provide acknowledgement of receipt of the notice and pay the administration and service fees.

When does the disqualification begin?

The disqualification takes effect 28 days from the date specified in the notice or 28 days from the date the notice was served. If you are already disqualified for another reason (for example, as part of a penalty imposed by a court), the drug driving disqualification begins once the other period of disqualification ends.

What if I receive a summons?

If you receive a summons to attend court, then the matter will be heard in court and you will have the opportunity to plead guilty or not guilty to the charge. If convicted, the court will determine and impose a penalty, including a disqualification period (if appropriate, and in line with any statutory requirements). It is recommended you seek legal advice prior to any court appearance.

Drug driving  :  Last Revised: Wed Apr 18th 2018
The content of the Law Handbook is made available as a public service for information purposes only and should not be relied upon as a substitute for legal advice. See Disclaimer for details. For free and confidential legal advice in South Australia call 1300 366 424.