skip to content
Law Handbook banner image

Drug driving testing

Roadside saliva testing

Since 1 July 2006, police have had the power to conduct random roadside saliva testing 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 saliva test and tests can be conducted anywhere in South Australia.

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. THC remains detectable for several hours after the drug has been taken and methylamphetamine and MDMA for a period of 24 hours.

Can I refuse a drug test?

Where a person has been required to submit to an alcotest or breath analysis [Road Traffic Act 1961 s 47E], they may also be required to submit to a drug screening test or oral fluid analysis [Road Traffic Act 1961 s 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. 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 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 random roadside saliva tests?

Only uniformed police officers who have received special training in saliva testing procedures will be authorised to administer roadside saliva tests.

How will random roadside saliva 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.

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 sample is recorded a second sample will be required for further analysis. This process will be conducted at either a ‘drug bus’ or police station and may take around 30 minutes.

Where a second positive sample is recorded the driver will then be interviewed and the sample sent to a laboratory for further 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 roadside saliva test?

A driver who tests positive for THC, methylamphetamine or MDMA 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)].

Drug driving testing  :  Last Revised: Fri Nov 17th 2017
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.