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Drink and Drug Driving
How alcohol and drugs affect driving performance
Alcohol impairs a driver's judgement and can cause a significant loss of control over a vehicle.
Drugs can impair a driver's overall alertness and particularly their ability to react rapidly to unexpected events. Drugs also increase the impairing effects of alcohol and fatigue.
Testing for alcohol
The method of detecting the amount of alcohol a driver has consumed is by determining their blood alcohol content.
The legal blood alcohol level is 0.05, meaning a driver's body must contain less than 50mg of alcohol per 100ml of blood. In Victoria, a blood alcohol level of 0.15 or more results in on-the-spot licence suspension until the case is heard in court. To detect a person's blood alcohol level a simple breath test is administered by police officers.
Testing for drugs
Driving while under the influence of drugs was made an offence under the Road Safety Act 1986 in December 2000. The legislation allows police to assess a driver they believe to be drug impaired. The assessment is based on observational eye and physical coordination tests. If the impairment assessor concludes that a driver is under the influence of drugs, the driver may be required to provide a blood or urine sample to test for the presence of drugs.
Drivers are required to take the test if directed by police and severe penalties exist for refusal.
Saliva testing for drugs
Under laws that came into effect in December 2004, Victoria Police have the power to conduct random roadside saliva testing to detect the presence of illicit drugs on motorists. There is a zero limit tolerance for the presence of illicit drugs while driving.
Drugs that are tested for include:
- cannabis
- speed (methamphetamine)
- ecstasy (MethyleneDioxyMethAmphetamine or MDMA)
Testing process
1. The first test is at roadside where a swab is used to collect saliva. The test takes only a few minutes to process. A blood sample can be taken should a driver not be able to provide a saliva sample.
2. If the result is positive the driver is taken into the roadside vehicle (either a booze bus or a specialised drug bus) and asked to do a repeat test.
3. If the sample taken inside the bus is also positive, that sample is sent to a laboratory for analysis.
Confirmation of the presence of illicit drugs in the sample will result in a fine or licence loss.