DUI…or Anemic?

Posted by Lawrence Taylor on September 26th, 2008

I’ve commented repeatedly in the past about the inaccuracy and unreliability of breath-testing devices used in DUI investigations. This is due to a wide range of factors, including inherent design defects (see, for example, my previous post “Why Breathalyzers Don’t Measure Alcohol”); ineffective calibration and maintenance of the machines; improper administration of the test; radio frequncy interference; and, most importantly, physiological variability in humans.

The main problem with breath machines is that they are designed to assume all human beings are the same (see “Convicting the ‘Average’ DUI Suspect”). In fact, we are all very different from one another in ways that are critical to such testing — and we are ourselves physiologically different from one moment to the next.

Each of us, for example, is inherently different in our partition ratio — the ratio of alcohol in our breath compared to alcohol in our blood — and this ratio differs within ourselves from hour to hour (see “Breathalyzers — and Why They Don’t Work”). This is critical, as the breathalyzer will automatically compute the amount of alcohol in the blood based upon the measured alcohol on the breath — using a uniform ratio that (falsely) assumes we are all the same. Another human variable is the existence of such conditions as diabetes (see “Diabetes and the Counterfeit DUI”), acid reflux (“GERD, Acid Reflux and False Breathalyzer Results”)…. and anemia.

A person suffering from anemia has a low red blood cell count, perhaps half as much as would be normal. Put simply, when there are fewer red blood cells, the body will increase the amount of plasma to fill the void. Red and white blood cells are solid; plasma is liquid. Alcohol is attracted to liquid in the body, not muscle, bone, or other solids. It follows that the higher the ratio of liquid to solids in the blood (called the hematocrit), the higher the amount of alcohol in the blood — and the higher will be the reading on the breathalyzer.

The male-female average hematocrit is 45% (men average 47%, women 42%), but the range varies for men from 42 to 52%, and for woman from 37 to 47%. The machine, of course, assumes that all suspects have a hematocrit of 45%. The effect of an individual’s hematocrit on breath analysis can be mathematically computed. The partition ratio of alcohol in blood to alcohol in breath uniformly used in breath testing is 2100:1. If the suspect’s hematocrit is, say, 54%, the breath test result could be computed by multiplying it by 45/54. Assuming a breath test result of .09%, for example, the true blood-alcohol concentration could be determined by the formula .11 x 45/54 = .07%.

In other words, a person with a true BAC of .07% but a hematocrit of 54% would test on an otherwise “accurate” machine as .09%.  The machine "proves" the innocent citizen guilty - just because he or she is anemic (or simply varies from the statistical norm).

  • koivisto

    There are so many variables, known and unknown that are not taken into account. The BAC number is used, end of sentence. Bottom line, get the evil drunk off the road, no matter the consequence.

  • David W

    And they will never be taken into account other than thru the efforts of a good attorney(ie: Larry). Its not about right or wrong,,its about labeling individuals period by any means possible. To create ammunition for the select few out there that feel “their will” is the rule we all should adhere to. Totally outside the realm of beliefs this country was founded upon.

    If we put up a fight, then dirty tactics come to play. Again, no right or wrong,,just trying to use the issue as an avenue to classify an individual as an un-individual in this society.

    They tried on me. They got caught with their pants down at the end. Three years to prove it, but three years well worth it.

    Their foolishness was beyond the comprehension of a normal person. Therefore, I consider them a threat from that day and will never change my stance. They tried to hurt me, but the end result was they hurt my children. Shame on them. There must be some kind of genetic failure out there as it appears some noses out there are far too long for the body that supports it.

    Their day is coming. Not from me, but from truth itself.

  • prosepa


    After receiving a DUI a couple of months ago I stumbled upon your site and have been checking it on a regular basis. When I was arrested I was taken to the hospital, read the implied consent warnings for PA, and refused blood. That was about 2 months ago. PENNDOT notified me my license would be suspended for 12 months for not giving my blood, which could have been used as evidence against me in a criminal case. As a Government and Political Affairs major I cannot believe that this has not already been ruled unconstitutional. I spent $115 to file an appeal through the court house and went to court today representing myself. I spent weeks doing research and my argument was that the Implied Consent law of PA violated my rights under Title 1, Section 9 or the PA Constitution: “…he cannot be compelled to give evidence against himself…” I got about 1 minute into my defense and the judge stopped me and asked the DMV attorney if this issue has already been raised. She referenced 5th Amendment case law and I explained this was a PA Con Law issue. The judge stopped me and said he’d heard enough and ruled in favor of the DMV.

    After my hearing I filled out an intake form for the local ACLU to see if I can get assistance in going to the appellate level, which I have no experience with. I know with everything I have that the implied consent law is a backdoor attempt by the legislature to have multiple arms of the state work together to gather evidence, yet claim it as a civil action. If the ACLU will not help me then I will try and figure out how to file my own appeal. I believe in the fundamental principles that the framers felt compelled to include in the written constitution of the state of PA and the U.S. Government.

    If I were in the situation again, I would again refuse to give blood, even if they threatened me with a seven year license suspension. People should not fear government; rather government should fear the people! This slippery slope, unconstitutional case law could easily lead to implied consent laws attached to marriage, fishing, hunting licenses. Or even better yet, let’s put an implied consent law with birth certificates. The state issues them, so they can take them away if you violate whatever they say you consented to. If you don’t like it, then don’t have kids, or don’t have a certificate of birth issued.

    I cannot lay down on this issue, and I will exhaust everything I have in an attempt to right this wrong.