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This issue arises when someone is arrested for DUI and he or she admits to having had two or three beers, but denies feeling the effects of the alcohol. But, the breath test reflects a 0.08% or greater blood alcohol concentration. How does this happen?

It’s been known for some time now that if someone was involved in a motor vehicle accident which resulted in blood in the mouth, that the blood being breathed in the breath testing machine will cause the machine to read at a higher level. Two things need to be addressed to understand the science involved in this issue. The first issue is how does breath alcohol testing work, and issue two, how does blood in the mouth or Gingivitis and Periodontal Disease affect a blood alcohol breath test?

Issue One: How does breath alcohol testing work?

Henry’s Law is a simple law of physics that says: if you put a liquid into a sealed vacuum container with a airspace or headspace above the liquid in the container, and heat the container to 34 degrees Celsius, then the liquid within the container and the contents of the headspace above the liquid will have the same molecular makeup. However, the makeup will be in a slightly different ratio since the means of suspension, i.e., air and liquid will be different.

In breath testing they assume for each molecule of ethanol in your breath there will be 2100 molecules of ethanol in your blood, i.e., the blood is the liquid in the sealed container, and the breath in your lungs is the airspace above the liquid. Now, the breath test machine applies this ratio mathematically to each and every molecule of ethanol it detects in the breath chamber. If blood is getting into the chamber, then the blood is going to have a higher concentration of ethanol than the machine expects to see. The machine will then take the number of molecules of ethanol in the blood sample and simply multiply it by 2100.The machine will not distinguish ethanol in blood and ethanol from the lungs.

This will give a false high reading. This accompanied by the fact that most breath chambers are only taking a small sample of breath compounds the problem.

Most statutes require that a determination of the grams of alcohol, pursuant to 210 liters of breath, is what is required to have a valid breath test. For example, the common definition of a presumption of intoxication is when you have a 0.08% or greater grams of alcohol pursuant to 210 liters of breath. If you have a 0.08% or higher BAC, that triggers a presumption of intoxication.

Now, 210 liters of breath is equivalent to 55 or 56 gallons. The human lungs do not contain 55 or 56 gallons, nor was there ever a machine built that would hold 55 or 56 gallons of air. Most breath machines capture a sample, either in real time or sometimes referred to as a ‘snapshot’ sample of the breath. A typical breath chamber can be anywhere from ½ cc to approximately 60 cc’s. The machine is then going to multiply the amount of breath captured in the sample chamber by anywhere from 2,000 to 4,000 percent so that the amount being analyzed is assumed to be 210 liters of breath. The problem is compounded when you first multiply by 2,000 to 4,000 percent to get an equivalent of 210 liters of breath. Then you multiply the number of molecules of ethanol by 2100.

If blood gets into the breath machine along with the breath, you can have a staggering result of a 0.15 to 0.18 BAC, and in fact the individual could be well below a .08 BAC at the time of driving. This is all a result of the mathematical process that goes on within the breath machine and when the machine is reading molecules of ethanol in blood and assuming that it is molecules of ethanol in air.

Issue Two: How does blood get into the mouth?

It has been known for some time, that when you have some kind of automobile accident or any other traumatic injury to the mouth, there can be blood in the mouth which would affect breath alcohol testing.

What I have been working on and developing with one of my expert witnesses is the affect of Gingivitis and Periodontal Disease in breath testing. Gingivitis can simply be defined as “bleeding gums”. The actual cause of this condition has to do with bacteria and plaque which buildup around the teeth. This causes the gum area around the teeth to become sensitive and will bleed. A lot of people do not take proper case of their teeth, and constantly experience blood in their mouth when brushing their teeth. One question I ask my clients is if when they brush their teeth or floss their whether or not they get blood in their mouth. Or when they spit out toothpaste, is there blood mixed with the toothpaste. If the answer is yes, you now have a serious issue that is going to affect the accuracy of breath alcohol testing.

The next area to be addressed is Periodontal Disease. Periodontal Disease results in periodontal pockets that are nothing more than a depression or pocket that develop next to the teeth where the bacteria next to the teeth has been eating away and creating small areas or pockets where blood and alcohol can be stored in the mouth. In these pockets, alcohol, food and blood can get trapped, so that when you perform a breath test, you are breathing food particles, along with blood and alcohol into the breath testing machine.

What needs to be understood and clearly spelled out, is that the Gingivitis and the accompanying bleeding problems associated with Gingivitis is a continuing process. Most breath testing procedures require a fifteen minute observation period of the subject prior to the subject breathing into the breath machine. This procedure is supposed to allow the evaporation of any potential mouth alcohol. When you have Gingivitis, it is a continuing and ongoing process. There is nothing the subject can do to stop the bleeding process, it is occurring the subject’s mouth. You can rinse your mouth out or wait all the time you want, but nothing is going to stop the bleeding of the gums. It is, as I stated, continuous. There is nothing anyone can do to stop this bleeding process. [Potentially seeing a Dentist and getting treatment for the condition can help.] In fact, according to my experts, the trauma to the gums of putting your lips around a mouthpiece and blowing into a breath testing device will in all probability increase the amount of blood getting to the breath testing machine, as it is causing more trauma to the gums that are already bleeding.

The two leading articles in this area are A Simulation of the Affect of Blood in the Mouth on Breath Alcohol Concentration of Drinking Subjects, by J.G. Wigmore and M. P. Wilke, published in Canadian Society of Forensic Science Journal, Volume 35, Number 1 (2002) pages 9-16. The other article is The Affect of Blood in the Oral Cavity on Breath Alcohol Analysis, by M. Chu, D. L. N. Wells, R. G. King, J. Farar and O. H. Drummer, published in the Journal of Clinical Forensic Medicine (1998) Volume 5, pages 114-118.

These two leading articles on blood in the mouth are helpful. In the Wigmore and Wilke article, the subjects even held blood in their mouths, then spit the blood out, waited ten minutes, then took a breath test. Their conclusion was that there was no significant affect of blood in the mouth. This was based upon the blood being spit out and a minimum ten minute observation period. This is clearly different than the theory being proposed here, inasmuch as the gums are continuously bleeding and it stays in the mouth, you cannot get rid of it.

In the other article entitled, The Affect of Blood in the Oral Cavity on Breath Alcohol Analysis, the results were quite significant for the defense. The test was broken into four stages, Stage A, B, C, and D. Stage A was a breath test before solution was put in the mouth. Stage B was with solution in the mouth. Stage C was with solution in the mouth. And Stage D was a test after the mouth was rinsed.

In all of the groups tested, during Stages B and C, WITH SOLUTION IN THE MOUTH a statistically significant increase in BAC was found. This would confirm that blood in the mouth through Gingivitis and potentially through Periodontal Disease causes a continuous bleeding in the mouth and there is nothing that can be done to prevent the contamination of the test and of the test giving a false high reading of the subject’s Breath Alcohol Concentration.

In every breath alcohol concentration (BAC) test, there is a great “margin of error” or “uncertainty”. This margin of error, or uncertainty, is a documented scientific fact.[1]

Every client I have represented who had a breath test, has had a margin of error in that breath testing that potentially worked in his/her favor.

In every DUI trial, there arises that point when the prosecution’s expert tries to relate the breath alcohol concentration (BAC) test result to the time of driving. It is key to the prosecution in any DUI case, to establish what the individual’s BAC was at the time of driving. It is essential to establish this in order to establish the crime. The BAC test is taken anywhere from 30 minutes to several hours after the time of driving. Therefore, to determine what the BAC was at the time of driving, the prosecution’s expert must engage in a process known as Retrograde Extrapolation, or as I like to refer to it, “voodoo science”.

It is imperative to the prosecution’s case that the prosecution’s expert establish what the BAC was at the time of driving. The prosecution’s expert will attempt to do this through testimony by estimating the number of drinks consumed by the defendant and testifying as to the BAC of the defendant at the time of driving.

It has long been known since the early 1930's, when Mr. Eric M. P. Widmark developed the first equations to calculate a blood alcohol concentration. Mr. Widmark determined that a degree of “uncertainty” exists in the establishing of a breath alcohol concentration. Mr. Widmark found two areas of “uncertainty”. He referred to one as the “rho factor” (food content in the stomach), and the other as the “B slope” (the burnoff or alcohol elimination rate).

Just recently, a new peer reviewed article has appeared expanding the number of areas of “uncertainty”. In his latest, and what I believe to be his seminal work, Rod G. Gullberg has raised the uncertainty issue to new level.[2]

There are really eight factors of uncertainty. They are:

1. Gender (male or female)
2. Weight
3. Rho factor
4. BAC at time of test
5. B slope
6. Time
7. Amount of alcohol in each drink
8. Amount of drinks consumed

Under the latest peer review article by Rod G. Gullberg, it has been determined that the estimation of the number of drinks, could be off as much as ± 25%. The estimation of the BAC at the time of driving could be off ± 42%.

These numbers show that breath alcohol concentration testing is at best a guess and at it’s very worst, voodoo science.

In his article, Mr. Gullberg points out that juries are often asked to consider and weigh a blood alcohol concentration. However, they are lacking appreciation of the uncertainty of these estimates. Juries tend to assign an unmerited amount of weight to the prosecution’s expert. In his conclusion, Mr. Gullberg stated that all forensic scientists should present when testifying, a reliable estimate of uncertainty along with their opinions as to any estimates of a BAC or an estimate of the number of drinks. For example, when a state expert renders an opinion that a person had five to six drinks, he should also admit to the jury that he could be off as much as 25%, which would mean the person had as little as three drinks or possibly as many as eight drinks. THIS IS JUST A GUESS.

When a state forensic expert is testifying as to the BAC at the time of driving, and assuming he renders an opinion that the individual had a .11 BAC at the time of driving, he should also admit to the jury that taking in the uncertainty into consideration, using an error factor of .42%, that would mean that the individual had as low a BAC as a .06 at the time of driving or a BAC as high as a .16 at the time of driving.

To put the significance of this uncertainty factor into laymen’s terms, imagine you are flying an airplane from Los Angeles to New York City. Assume at the half way point in your trip, the pilot comes on the speaker and says, “We’ll be on time to land today, but we might miss New York City by a few thousand miles ending up in possibly Maine or Virginia.” Would you want to fly on that plane or on that airline ever again? The answer is no. Then why should a jury believe a breath alcohol concentration test result that can be off by ±42%?

If the state expert does not in his direct testimony, give this uncertainty, then it certainly incumbent on defense counsel to draw these numbers out of him and at the conclusion of the case, I’m sure that the defense counsel would say to the jury as I would say, “Ladies and gentle men, you’re not dealing with true science as being presented here today, you’re dealing with voodoo. When you have a scientific estimate, it’s expected to be scientific-- not a guess!"

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[1]Uncertainty Analysis for Forensic Science: Raymond M. Brach and Patrick F. Dunn; Lawyers and and Judges Publishing Company, Inc. 2004

[2]“Estimating the Uncertainty Associated with Widmark’s Equations as Commonly Applied in Forensic Science”; Rod G. Gullberg, Journal of Forensic Science International, 172 (2007) pages 33-39.

Keifer Sutherland was all ready on Probation for a 2004 DUI Arrest when he got arrested again.

Sutherland could spend up to a year in jail on this new DUI. It was his Fourth DUI. However, the DUI look back period is 10 years so only the 2004 can be alleged. The other DUIs are too old to be alleged, but could effect sentencing.

It is curious to note that Paris Hilton and Britney Spears got into additional trouble by continuing to drive when their Driver's Licenses where suspended. Sutherland could get up to a one year suspension of his driving privilege because of this new DUI.