In my previous post, “Are Women More Likely To Be Convicted of DUI?”, I discussed how today’s drunk driving laws and evidence tends to discriminate against women — specifically, I cited a scientific study showing how the lower levels of the enzyme dehydrogenase that breaks down alcohol are lower in women. However, this is just one example of the problem.
In another study, scientists found that women have lower “partition ratios” of blood to breath. All breath machines in DUI cases measure the amount of alcohol in a person’s breath. But the what we really want to know is the amount of alcohol in the person’s blood, so a small computer in the breathalyzer multiplies the amount of alcohol it detects in the breath sample by 2100 times. This is because, on average, there are 2100 units of alcohol in the blood for every unit of alcohol in the breath.
According to the study, women have a significantly lower partition ratio. Jones, “Determination of Liquid/Air Partition Coefficients for Dilute Solutions of Ethanol in Water, Whole Blood and Plasma”, Analytical Toxicology 193 (July/August 1983). And the lower the ratio, the higher the reading — even though the true BAC does not vary. Example: a woman with a true BAC of .06% and a ratio of 1500:1 (rather than the presumed 2100:1) will get a reading on the machine of .09% — above the legal limit for DUI. Put another way, the breath machine will show an average man accused of drunk driving to be innocent — but a woman with the same blood alcohol level to be guilty.
Lawrence Taylor is the co-author of the leading textbook in the field, Drunk Driving Defense, is certified as a Senior Specialist in DUI Defense., and is a former Dean of the National College for DUI Defense. If you need to consult with a Los Angeles DUI attorney, Orange County DUI attorney or Riverside DUI attorney, contact The Law Offices of Taylor & Taylor at 1(844)DUI-XPRT. With offices in Los Angeles, Orange and Riverside counties, the firm has limited its practice to DUI defense exclusively for 35 years and is consistently top-rated in surveys of Southern California lawyers and consumers.