Frequently Asked Questions

New and revised laws were introduced in Western Australia in October 2007, with penalties amended as of 1 October 2011,  to reduce the incidence of drug driving and the number of people killed and seriously injured as a result of drug driving. Although research consistently shows that alcohol is the major problem in relation to impaired driving, there is increasing concern regarding the incidence of other drugs and their contribution to road deaths and serious injury. There are a range of drugs other than alcohol that affect driving performance, increase crash risk and negatively impact on road safety. Studies have shown that drugs that are capable of impairing driver skills have been found in significant numbers of drivers who have been injured or killed on our roads. The drugs of major concern from a road safety perspective are THC (the active ingredient in cannabis) and amphetamine type stimulants including methylamphetamine (‘speed’ or ‘ice’) and MDMA (‘ecstasy’).

Essentially, the 2007 drug driving laws made provision for two new offences within the Road Traffic Act 1974: Driving with the presence of a prescribed illicit drug in oral fluid or blood; and Driving while impaired by a drug.

The 2007 drug driving laws also allowed for the introduction of random roadside drug testing, where drivers stopped by police may be required to provide a saliva sample to be tested for drugs. Random drug testing focuses on identifying the presence of a prescribed illicit drug in the salvia or blood of a driver and does not attempt to quantify any level of impairment. Random drug testing is focused on the detection of recent use of prescribed illicit drugs: THC (the active ingredient in cannabis), methylamphetamine (‘speed’ or ‘ice’) and MDMA (‘ecstasy’). The new and revised laws also focus on driver impairment and are concerned with identifying and prosecuting drivers who are visibly impaired by drugs. In the first instance, the impaired driving legislation relies on visual evidence of possible driver impairment by a police officer, followed by standardized assessment procedures. Where drug impairment is suspected, a blood and urine sample is collected. The police report and the blood/urine tests results are then reviewed and, where expert opinion supports the police and toxicological evidence, a drug impaired driving charge will result.

New penalties were then introduced as of 1 October 2011.

Random roadside saliva testing for prescribed drugs is part of the Western Australian Government’s commitment to improving road safety, reducing road trauma and associated costs to the community. The rationale for random roadside drug testing is to increase the detection of drivers that may pose a potential risk on the road and prevent them from driving for a period of time. Similar to random breath testing, random drug testing provides a visible form of deterrence to those that may choose to drive after using a prescribed illicit drug and institutes appropriate penalties to act as a future deterrence to drug driving.

In 2003, Victoria was the first place in the world to trial random roadside drug testing. South Australia followed in 2005, Tasmania in 2006 and NSW in 2007. The experience gained in the other states has informed and helped shape the drug driving laws in Western Australia and information will continue to be shared between the states into the future.

Yes. The 2007 legislation requires a review to be conducted after 12 months of operation so that the effectiveness of the initiative and whether there is a need for any additional legislative or operational changes can be assessed. The review must be tabled in Parliament with 18 months of commencement (due April 2009). The Government will also continue to closely monitor developments in other states in regard to drug testing of drivers.

Random roadside saliva testing is used to detect the presence of THC (the active component in cannabis) and methylamphetamines (including MDMA), which are, after alcohol, the drugs of greatest concern in relation to road safety.

THC (the active ingredient in cannabis) can be detected in saliva for up to four hours after use, but is dependent on the amount and potency of the cannabis, on the individual’s metabolism and the method of use. THC residue from using cannabis in previous days or weeks will not be detected. Methylamphetamines, including MDMA, can be detected for approximately 24 hour after use. Extremely large doses, a person’s metabolism and whether other drugs were taken at the same time may affect the duration of the effects of these drugs.

Having THC (the active ingredient in cannabis) in saliva as a result of passive smoking would be very unlikely and if it was evident it would be at extremely low levels that would not be detected by the screening devices.

Random saliva testing is only used to detect the presence of THC (the active ingredient in cannabis) and methylamphetamines, including MDMA. Drivers found to be impaired by any drugs will be prosecuted for the new and more serious offence of driving while impaired by a drug. This will apply in instances where a police officer witnesses driving behaviour that indicates that a driver’s ability to drive is impaired and where that suspicion is confirmed following driver assessment and blood, not saliva, tests.

The roadside saliva tests will only detect THC (the active ingredient in cannabis) and methylamphetamines, including MDMA. The tests will not detect the presence of prescription drugs or common over the counter medications, such as cold and flu tablets, sinus medication (eg Sudafed), asthma and ADHD medication.

Any driver in Western Australia may be required to undertake a roadside saliva test for recent consumption of cannabis and methylamphetamines, including MDMA.

Saliva samples are relatively easy to collect and can be screened easily using a quick and accurate method to detect the presence of the prescribed drugs. Taking a saliva sample is less intrusive than other sampling techniques (such as taking a blood sample).

Before undertaking a roadside drug test, drivers are required to complete an alcohol breath test. Drivers may also be requested to provide a saliva sample for drug testing by placing an absorbent swab in their mouth or touching it on their tongue until a sample is collected. The saliva sample will be screened at the roadside, with the result determined within about five minutes. If a positive result is determined, a second sample will be required for further analysis. This process requires the driver to leave the vehicle and accompany the police officer to the Bus or other place, which may take around 30 minutes. Drivers who return a negative saliva and alcohol test will not be detained further. Penalties apply where drivers refuse or fail to undertake a drug test when required to do so by a police officer.

Saliva testing is an accurate and reliable method for detecting the recent consumption of THC and methylamphetamines including MDMA. The drug testing devices used must meet rigorous standards of accuracy. No charges against the driver are laid until the presence of the prescribed drugs has been confirmed by a full laboratory analysis of the second saliva sample or a blood sample.

Only police officers who have been specially trained both in the use of the testing equipment and testing procedures are permitted to administer roadside saliva tests.

Roadside saliva testing may be conducted anywhere, at any time, in Western Australia.

A roadside saliva screening test takes around five minutes. Where a positive result is obtained, the driver is required to undertake a second saliva test or provide a blood sample to confirm the presence of the prescribed drug. In most cases, the confirmatory saliva test takes around 30 minutes.

The roadside saliva screening test can be conducted through the driver’s window, in a similar way to alcohol testing. However, for safety and other reasons, police may require a driver to exit their vehicle to undergo a preliminary breath test or roadside saliva test. A driver who returns a positive result to the initial saliva test is required to leave their vehicle and accompany the police officer to the Bus or other location in order to provide a second saliva or blood sample for further testing.

Under the legislation a driver is required to undertake the drug test and penalties for refusal apply.

A driver who is unable to supply the required saliva sample because of a medical or physical condition may supply a blood sample instead. Taking of blood samples can only be conducted by approved and suitably qualified professionals.

Yes. A driver who tests positive is required to undertake a confirmatory saliva test or provide a blood sample for further analysis. Similar to current drink driving legislation, drivers are given a part of the saliva or blood sample to have their own analysis done if they wish.

Police will inform drivers within a few weeks of the results of the laboratory analysis. Before any charge can be laid, the presence of THC, methylamphetamines or MDMA must be confirmed. If the laboratory analysis confirms the presence of these drugs the driver may be charged with driving with the presence of a prescribed illicit drug in oral fluid (saliva) or blood.

A driver who tests positive to THC or methylamphetamine (including MDMA) is advised by police not to drive until the drug is no longer in their system (up to 24 hours). If they attempt to drive away they may be arrested on suspicion of attempting to drive with a prescribed drug in their system. The legislation also gives Police the power to confiscate vehicle keys in circumstances where they believe that the driver is at risk of continuing to drive the vehicle.

A driver can be charged with the new offence of: driving with a prescribed illicit drug in oral fluid or blood; or driving while impaired by a drug.

Under the legislation, all saliva and blood samples must be destroyed following the conclusion of all prosecution proceedings and appeals. Saliva and blood samples collected for the purpose of roadside drug testing are not to be used for DNA testing.