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Drugs and driving

It is against the law to drive under the influence of alcohol or any illicit drug.

Mobile drug testing is used in NSW. Police can administer an oral drug test to any driver. Cannabis, ecstasy , cocaine and methamphetamines can be detected through roadside testing. A person who tests positive is prohibited from driving for 24 hours. The sample is sent to a laboratory for more precise analysis, and if the presence of an illegal drug is confirmed the driver may be charged.

A person can also be arrested and taken to a hospital for a blood and urine test if a police officer has a reasonable suspicion that they are driving under the influence of drugs. 

Random driver drug testing

It is an offence under the Road Transport Act 2013 (NSW) to drive with THC (the psychoactive ingredient of cannabis), cocaine, methamphetamine or ecstasy ‘present’ in the driver’s saliva, blood or urine (although only saliva is usually tested).

The police are allowed to conduct random roadside testing of drivers to test for the presence of these drugs. The roadside tests involve a saliva test using drug screening equipment. If the initial saliva test indicates positive, then the driver must undertake a second saliva swab at a mobile drug bus or police station.

The second sample is sent to the laboratory for analysis, whether it is positive or negative. But if the second swab shows positive, the police issue the driver with a direction not to drive for 24 hours. If the laboratory analysis confirms the presence of THC, cocaine, methamphetamine or ecstasy, the driver is issued with a court attendance notice for the offence. It is the analysis by the laboratory, not the roadside test results, which the police rely on as evidence in court.

It is also an offence to drive with morphine present, but this substance will not be detected by saliva swab.

Offences and penalties related to driving under the influence of alcohol and drugs in NSW.

Driving under the influence

It is an offence under the NSW Road Transport Act 2013 to drive 'under the influence' of a drug or alcohol. Proof of this offence requires proof beyond reasonable doubt that the driver was intoxicated to some degree by the drug or alcohol.

Since the introduction of breathalysers and random breath testing for alcohol, drink driving offences are now much more commonly charged as driving with the relevant 'prescribed concentration of alcohol' under the Road Transport Act 2013 (NSW). This in effect bypasses any need to prove intoxication—the presence of a particular concentration of alcohol in a person's system is sufficient evidence for the offence to be proved.

Offences and penalties related to driving under the influence of alcohol and drugs in NSW.

Under the Crimes Act 1900 (NSW) a person convicted of driving under the influence of a drug and causing death is liable for a maximum penalty of 10 years' jail (or 14 years if there are circumstances of aggravation such as speeding).

Drug testing

If the police reasonably suspect that a person is driving under the influence of a drug, they have the power to take them to a hospital for a blood or urine test for the presence of drugs, under the supervision of a doctor. 

It is an offence to refuse to submit to a blood test or a urine test in these circumstances. It is likewise an offence to wilfully alter the amount of drug in your blood or urine before having the test, unless it is more than two hours since you were driving.

The information on this page was originally published in The Quick Guide to Drugs and Alcohol. It has been updated to reflect changes to the law.