The rules outlined below are an overview, please refer to the rule references for more details.
Professional drivers such as truck, bus or taxi drivers; P-platers and learner drivers must have a zero blood alcohol concentration (BAC), while all other drivers must stay under .05 BAC. You must be under .05 BAC while supervising a learner driver. This rule applies to public roads and also private property.
It is illegal to drive while impaired by any drug whether that drug is legal or illegal. You must not be affected by illegal drugs while accompanying a learner driver. This rule applies to public roads and also private property.
It is an offence to refuse to provide a breath or blood sample or stop at a booze bus (or Random Breath Test station), or fail to cooperate in the conduct of a breath or blood test.
It is an offence to refuse to stop at a Random Drug Test station or provide a saliva sample. Roadside testing for illegal drugs is conducted using a saliva sample. A driver provides a sample by placing an absorbent collector in their mouth or touching it with their tongue. The test takes around five minutes. A saliva test must be confirmed by laboratory testing before any charge can be laid.
Road Safety Act 1986, Part 5 - Offences involving alcohol or other drugs
To look up these rules and check for other related rules, please refer to the Acts and Regulations administered by VicRoads.