Elements of the offence

A person who drives, or who attempts to drive, a vehicle while so much under the influence of alcohol or a drug as to be incapable of exercising effective control of the vehicle is guilty of the offence of driving under the influence [Road Traffic Act 1961 (SA) s 47].

Can be charged with DUI even if under legal limit

The charge of driving under the influence is not the same as driving with the prescribed concentration of alcohol and it is possible to be convicted of driving under the influence of alcohol even if the blood alcohol level is less than the prescribed concentration. It is not unknown for people to be convicted of driving under the influence with a blood alcohol level of 0.04 of alcohol per 100mls of blood or even less. For the purposes of this offence, a person is deemed to be incapable of exercising effective control of a vehicle if any physical or mental faculty is lost or appreciably impaired. For the penalties, see alcohol and drug penalties.

Evidence of DUI

The prosecution may attempt to prove charges of driving under the influence by bringing evidence of the manner in which the vehicle was being driven and of signs of intoxication (including observations by the police and other witnesses), the smell of alcohol about the driver, unsteadiness, watery or bloodshot eyes and slow or slurred speech.