BREATH ANALYSIS TEST HELD TO BE UNRELIABLE

December 1, 2011

On 1 December 2011 the Full Court of the Supreme Court upheld a decision to dismiss a charge of driving with the prescribed concentration of alcohol on the basis that the person charged had shown that the breath analysis reading was unreliable.

The defendant in that case was charged with driving with a blood alcohol concentration of 0.098% after a breath analysis was conducted by police at 10.20 pm.  He exercised his legal right to have a sample of blood taken for analysis and that occurred at 12.30 am.  The result of the analysis of that blood sample was that it contained a blood alcohol concentration of 0.034%.

A forensic scientist with expertise in blood alcohol analysis gave evidence about the way in which the body absorbs, metabolises and eliminates alcohol and expressed the opinion that the defendant’s blood alcohol concentration at the time of the breath analysis was around 0.06% – less than the reading given by the breath analysing instrument.

The Supreme Court held that the difference between 0.098% and 0.06% was significant and that therefore the breath analysis reading was exaggerated.  The legal presumption that the reading obtained by the breath analysis was to be regarded as the blood alcohol concentration at the time of driving was therefore rebutted and the charge was dismissed.

This case highlights the importance of thoroughly investigating the reliability of the breath analysing instrument before accepting that the reading obtained is correct.  Websters Lawyers in Adelaide can help you to understand how the laws relating to drink driving and breath analysis tests operate and what steps you can take to ensure you make an informed decision regarding  these types of charges.

Police v Douglas [2011] SASCFC 148