Breath analysis vs blood analysis: no difference, says NSW Court of Appeal

Downing Centre Local Court, Drink Driving, Recent News, Sydney Supreme Court, Traffic Law

Suppose you are subjected to a roadside random breath-test one Saturday morning. You had some drinks the evening before, and you blow 0.063, putting you above the legal limit of 0.05. You are taken to the local police station, where in accordance with ordinary procedures, you are subjected to a breath analysis, which returns a result of 0.054, a little lower, but still above the limit. As is your right, you request a blood analysis, which takes place almost one hour later, and returns a result of 0.049, which puts you UNDER the legal limit by a whisker. You are charged with low-range drink-driving. Does the Court rely on the breath analysis, or the blood analysis? Do you win or do you lose?

This was the precise situation Thomas Bignill found himself in when he was charged with drink-driving on 19 April 2014 at Neutral Bay. After the charge was dismissed by Magistrate Pierce in the Downing Centre Local Court, the Director of Public Prosecutions (DPP) took over the matter and appealed it to the Supreme Court, where Justice Adamson granted the DPP’s appeal. Bignill appealed to the Court of Appeal, and lost.

The Court of Appeal held that Sch 3 cl (31) of the Road Transport Act 2013 provides that EITHER the result of the breath analysis or the blood analysis may be relied on by the prosecution as presumptive proof of what the defendant’s blood alcohol concentration was at the time they were driving. Importantly, the court held that there is no preference either towards blood results or breath results. The only potential relevance differing results could have could be in the situation where the breath result is vastly higher than the blood result – which might suggest that the breath analysis equipment was faulty. In that case, the defendant would have a chance at satisfying the relevant legal test, which is, that on the balance of probabilities, it was more likely than not that at the time of driving, their blood alcohol concentration was under the legal limit.

The decision makes sense. If Bignill were successful, it would mean that drivers who blew over the limit at the roadside breath test could wait around until their breath is analysed at the police station, and if just over the limit, wait around a bit longer until a person qualified to take blood (that is, presumably a nurse and not a constable), is made available and takes the blood. Precious minutes, in this case, around one-and-a-half hours, elapse by the time the blood test is taken, giving the driver the opportunity for their blood to return to the legal limit. It would provide drivers an opportunity to ‘game’ the system, and rely on their state of intoxication hours after their driving, which is a bit of an unfair advantage. (Notwithstanding that blood alcohol concentrations can increase after driving (for instance, if you down a bottle of whiskey moments before being pulled over and breath tested).)

This decision makes it clear: if EITHER the breath analysis or the blood analysis shows you to be over the limit, you’re cactus (and perhaps you should have faked some chest pains, but that’s not something we would joke about).

You can read the Court of Appeal decision here.

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Image credit: Emma Partridge and Sydney Morning Herald

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Breath analysis vs blood analysis: no difference, says NSW Court of Appeal