O.C.G.A. § 40-6-391 makes it a crime to operate a motor vehicle if your blood alcohol concentration (BAC) is 0.08% or higher. Under Georgia’s DUI law, you are per se DUI if your blood alcohol concentration is 0.08% or higher—whether you are a man or a woman. Scientific evidence supports the conclusion that Georgia’s DUI per se statute unfairly discriminates against woman because the Intoxilyzer 5000 (Georgia’s breath testing machine) does accurately control for the physiological makeup of women. 

Researchers have found that the stomach lining of women contains less of an enzyme called gastric alcohol dehydrogenase than men. This enzyme is responsible for breaking down alcohol.  As a result of this lesser amount of enzyme in the stomach liner of women, researchers found that women reached the same levels of blood alcohol as men after drinking only half as much (with weight differences taken into account). Researchers also found that women reached BAC levels illegal in a DUI case after drinking 20-30% less alcohol than men. 

Also, researchers have found that the “partition ration” of blood-to-breath in women is lower than the same ratio in men. Georgia’s breath testing machine—the Intoxilyzer 5000—reaches a measurement of a person’s BAC by measuring the amount of alcohol in a person’s breath.  However, the DUI law is allegedly not concerned with the amount of alcohol in a person’s breath.  After all, it is a person’s blood that allegedly impairs a person’s central nervous system.  Therefore, the Intoxilyzer 5000 must extrapolate from the content of alcohol in a person’s breath to determine the amount of alcohol in their blood. 

The Intoxilyzer 5000 calculates the blood-alcohol content (BAC) of a person by multiplying the alcohol content in the breath sample by 2100. The Intoxilyzer 5000 assumes that there are 2100 units of alcohol in a person’s blood for every 1 unit of alcohol in a person’s breath.  However, research has shown that the ratio of blood-to-breath in women is actually much lower than 2100:1. As a result, Intoxilyzer 5000 often provides an artificially high BAC result for women. 

Research has also shown that women taking oral contraceptives reach their peak BAC faster (and return to lower levels quicker) than women not taking oral contraceptives. Georgia’s DUI law is concerned with the BAC of a person at the time that they are operating the motor vehicle. This research suggests that women taking oral contraceptives may be able to take the position that they consumed alcohol just prior to driving and that they did not have a BAC of 0.08% or greater at the time that they were operating the motor vehicle. 

Additionally, research has shown that women taking oral contraceptives or those pregnant had higher levels of acetaldehyde on their breath, due to their diminished ability to metabolize the enzyme as the level of sex steroids increases. Because the Intoxilyzer 5000 uses infrared analysis to measure the breath sample of a DUI suspect and the machine does not actually measure alcohol (it measures any compound in the molecular structure of the “methyl group” and acetaldehyde is one of these compounds), women frequently produce an artificially high breath test result. 

This discussion of possible sources of gender bias in testing conducted upon women with the Intoxilyzer 5000 is by no means exhaustive. There are numerous other medical and physiological issues that may impact the validity of the breath test in your case.  You must be certain that the attorney you retain understands both the law and the science of the state-administered breath test.