When you drink an alcoholic beverage, the alcohol circulates through your body and your bloodstream. As it passes through your lungs, it creates a measurable vapor. This is what breath-testing machines detect. The more you drink, the higher the concentration of vapor in your lungs the machine can allegedly detect.
The problem is that some of these machines do not always work as designed. They create false positives that result in people ending up under arrest when their blood alcohol concentrations did not reach the legal limit, which is .08 for individuals over the age of 21 here in Arizona. Other limits apply if you have a CDL or are under the age of 21.
What could go wrong?
Law enforcement officers and government officials would like you to think breath-testing machines are never wrong, but that simply isn't true. The machines could pick up other forms of ethyl alcohol that you didn't ingest such as acetone, butane and methane. Other substances you ingest, or medical conditions such as those listed below, could also result in a false positive:
- Asthma or other respiratory conditions
- Crohn's disease
- Prescription inhalers
- Flu and cold medicines
- Weight loss diets
- Regular tobacco use
- Recent use of mouthwash
Alcoholism can also produce a false positive. If you did have a problem with alcohol but happened to be sober when an officer pulled you over, you could still end up under arrest after a roadside breath test. Diabetes and high fat, low-carb diets (such as the Keto diet) can produce a significant amount of acetone to build up in your body, which could cause a false positive BAC just as substances in the air could.
Challenging the results of the breath test
As you can see, challenging the results of your breath test isn't just a crazy idea after all. Not only could the above-mentioned issues skew the results, but other issues could affect it as well. If the machine isn't properly calibrated or the officer fails to adequately perform the test, the results could not accurately reflect your true BAC.
If the "evidence" from the breath test fails to meet with court standards, then the charges against you may not stand. Determining whether something interfered with accurate results on your test could require some assistance from an experienced legal advocate.