In a case of driving under the influence of liquor, the state must prove that the accused drove a vehicle on a public road while under the influence, or while the alcohol content of the accused's blood exceeded 0,05g per 100ml.
When these elements have been established, a court will consider, in imposing sentence, the degree to which a motorist was under the influence of liquor, the extent to which his or her ability to drive was affected, traffic conditions at the relevant time, the type of vehicle being driven and the actual harm or danger caused by his or her driving. It will also consider the time and place of the offence, and whether the accused is a first offender.
Evidence against the accused may be given by the police, the examining doctor or any person who, at the time of the alleged offence, thought the accused was under the influence.
The opinions expressed in court must be qualified by reasons. For instance, the statement 'I believe he was under the influence' is not acceptable evidence, unless it is followed by an observation such as 'because he smelt strongly of liquor and his speech was slurred'.
In determining a sentence for driving with excessive alcohol in the blood, a court will consider the manner of the accused's driving at the time of the offence. Driving slowly and with exaggerated caution may be a characteristic of inebriation as erratic or reckless driving is. Imprisonment without the option of a fine is not usually imposed on a first offender, except in serious cases, such as when the accused was heavily under the influence or guilty of recklessness or gross negligence.