This Raleigh/Durham/Cary DUI/DWI attorney would like to comment on breathalyzers and specifically whether or not they are biased against women. Now I must tell you right off the bat that there are all kinds of problems with the accuracy and reliability of breathalyzers (more on that in the future) – but for now I am simply considering whether or not breathalyzers discriminate against women. The answer appears to be “yes”.
The explanation as to why this may be the case is a little complicated, so bear with me. First, any breathalyzer machine attempts to calculate a subject’s blood alcohol level by measuring the amount of alcohol in the breath (well, actually the amount of the methyl compounds in the breath). In doing so, the breathalyzer makes a major assumption: it assumes that each subject has 2100 units of alcohol in his/her blood for every one unit of alcohol in his/her breath. Based on this assumption, the machine then multiples the units of alcohol detected in the breath by 2100 to calculate the blood alcohol level.
This process would work fine if everyone had an alcohol blood-breath ratio of 2100:1. And do they? No! Scientists have found that people can have an alcohol blood-breath ratio of anywhere from between 1100:1 to 3000:1. And this variation can have an enormous impact on the results of a breathalyzer test. For instance, if your blood-breath ratio is actually 1500:1 (rather than 2100:1 as the breathalyzer assumes) the breathalyzer will calculate your blood alcohol level as 0.10%, when it really is only 0.07%. So, if your blood-breath ratio is lower than normal, the breathalyzer will falsely inflate your blood alcohol level. And scientists have found that what group has lower-than-normal blood-breath ratios? Women.
