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Defences to Drink Driving Charges


In the vast majority of drink driving cases offenders plead guilty as there is no valid defence open to them. However, that does not mean that you cannot successfully defend a drink driving offence. Armstrong Legal has successfully won many drink driving cases for a number of different reasons.

This article sets out some of the more common ways in which a drink driving charge can be defended. You may be surprised how many different ways there are to defend a drink driving charge.

Challenge the reading

The police use alcoholmeters to measure a person’s Prescribed Concentration of Alcohol (PCA). These machines are usually very accurate and well maintained. Challenging the accuracy of an alcoholmeter is usually not easy. But it is sometimes possible to prove that the reading produced by the alcoholmeters is not the same as the reading you had at the time of driving.

Remember, the offence is driving while over the legal limit. This means that what is important is your reading at the time that you were driving. Because your blood alcohol level goes up and then down over time, the reading you get from the alcoholmeter might not be representative of your blood alcohol content at the time of driving. Given enough information, scientists can calculate a person’s likely reading at the time of driving.

What all this adds up to is that sometimes it is possible for us to prove that, although you were over the limit at the time of your breath analysis, you were not over the limit at the time you drove, hence you are not guilty of drink driving.

Whether it is worthwhile to pursue this kind of defence depends on a number of factors including your reading, how much alcohol you drank, when you drank it and how much and what you ate on the day. Our lawyers will be able to advise you whether in your particular circumstances the defence may apply.

Honest and reasonable mistake

Contrary to popular perception, it is a defence to a PCA charge if you honestly and reasonably thought that you were under the limit at the time of driving. Simple though it sounds, in practice, being able to show that your belief in your own sobriety was reasonable can be challenging, especially in the current social climate in which drink driving is increasingly seen as inexcusable.

Our traffic lawyers can discuss your particular situation with you and advise you whether we think you may have this defence open to you.

Police failed to breathalyse within two hours

It is a little known fact that the police are not allowed to require you to undertake a breath test if more than two hours have passed since you last drove a car. What this means is that if you were tested more than two hours after you drove, it may be possible to have the evidence of your intoxication excluded.

Police breath-tested you at home

It is illegal for the police to require you to submit to a breath test at your home. If the police act illegally we may be able to have the evidence of your reading excluded.

It is important to make it clear that neither the author of this article nor Armstrong Legal encourages or endorse drink driving. However, we also passionately believe that every individual is entitled to know what their legal rights are. The purpose of this article is to provide you with information about your legitimate legal rights to defend a PCA charge.

If you require legal advice or representation in any legal matter, please contact Armstrong Legal.

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