1 Driving or being in charge of a motor vehicle under the influence of alcohol (DUI);

2 Driving or being in charge of a motor vehicle while the blood alcohol content (BAC) exceeds or is equal to the prescribed limit of 0.05;

3 "Fail the test" offences;

4 Refusing a breath test or failing to undergo a blood sample in hospital after a motor vehicle accident;

5 Failure to have a zero blood alcohol (for Probationary license holders); and

6 An accompanying driver offence.

Penalties for blood alcohol offences usually involve fines or imprisonment or license or permit disqualification. License or permit penalties for drink-driving offences involving BAC readings vary according to the nature of the driver's BAC, prior drink-driving offences, and when the offence took place.

Conviction for more serious offences like DUI or refusing a breath or blood test, involves two years' license disqualification for a first offence and four years license disqualification for subsequent offences.

Conviction for BAC reading offences involves license disqualification on a sliding scale according to the BAC reading. The period of disqualification is doubled for a subsequent offence.

As a result of the Road Safety (Amendment) Act 2000 (Vic.), drink-drivers with readings of 0.07 or above must have their license cancelled, irrespective of whether they were issued with a traffic infringement or a summons to appear in court. Magistrates have no discretion to alter the period of cancellation. Drink-drivers with alcohol readings of 0.05 or 0.06 may retain their licenses subject to incurring 10 demerit points whereupon VicRoads has the power to suspend or cancel licenses and permits.

Whilst difficult, it is possible to challenge BAC readings successfully. These defences are generally based upon expert evidence, using the breathalyser over-estimation and rise and fall arguments. These defences are confined to offences of being in charge of a motor vehicle while the blood alcohol content exceeds the prescribed limit.

It is more difficult to challenge "fail the test" offences where a driver has, within three hours of driving or being in charge of a motor vehicle, provided a breath sample or a blood sample which, when analysed, exceeds the prescribed BAC. In relation to those offences, challenges appear to be limited to situations where the elements of the offence are not made out. In other words, defences are that the defendant was not driving; the test was not done within three hours of driving; or where the defendant can establish that the BAC was solely due to the post-driving consumption of alcohol; or the breathalyser was on the occasion not in proper working order or not properly operated.

It is also becoming increasingly common for drink-driving charges to be challenged on grounds that the Police have failed to comply with the drink-driving legislation.

It is important for clients to seek legal advice, particularly where BAC readings are alleged to be 0.07 or above.