Problems with DUI blood samples at State Toxicology Lab

I am often troubled when the criminal justice system fails to take proper steps to guarantee that evidence used is scientifically reliable.  Juries give a lot of credibility to expert witnesses who come to court to testify about evidence found in a criminal case.  The experts, however, are often not very thorough in making sure that the proper steps are followed in collecting the evidence.  Lawyers should be alert to these flaws.

I was recently defending a man accused of an alcohol-related driving charge, where a blood sample was taken at the hospital to test for alcohol content. The person taking the sample filled out the form describing how he drew the sample. At the bottom of the page on the blood draw form, the lab worker is called upon to fill in a box stating: “Chemical Used to Sterilize the Area.” The phlebotomist wrote in the word “water”. This was perplexing. The only explanation for this gross lapse of scientific standard is that the phlebotomist was aware that an alcohol based sterilizer could not be used, but he was unaware of what sterilizer could be used (iodine). It is important to take note that the sterilizing agent is not just used to protect the patient from infection, it is critical to protecting the integrity of the blood sample. As one scientific journal has explained: “The venipuncture site must be cleaned with an antiseptic prior to venipuncture. Otherwise microorganisms from the skin could be picked up by the needle and carried into the vein, creating the possibility of infection, or flushed into the collection tube on blood flow, contaminating the specimen.” See the publication Phlebotomy Essentials, 3rd Ed., McCall and Tankersly, 2003, pp. 245-246.  Contamination of the specimen is exactly what everyone should be trying to avoiding in a DUI or DWI case. The accuracy of blood results are threatened by bacteria. One such bacteria is Candida albicans. “Candida albicans is a diploid fungus (a form of yeast). . . under normal circumstances, C. albicans lives in 80% of the human population.” See // The presence of this yeast in blood samples can lead to dramatic increases in alcohol levels even in samples containing preservative, particularly when the sample is not properly refrigerated.   See The Effects of Temperature on the Formation of Ethanol by Candida Albicans in Blood, Chang , J. and Kollman, S.  E., Journal of Forensic Science, JFSCA, Vol. 34, No. 1 pp 105-109.  (1987).    Studies show blood alcohol appearing in samples that previously had not had blood alcohol present, and in amounts up to .05%.  So, a person who is accused of driving with a high level of alcohol in his blood stream in a DUI case, needs to look at his case very carefully to see how the sample was collected.  This sample in question was drawn from a hospital right in Stevens County Washington.   This problem needs to be looked out for because it is not uncommon.  As one medical journal has put it:  “The most common source of contaminated percutaneous blood cultures is often thought to be the skin of the patient at the site where cultures are obtained.”  See Updated Review of Blood Culture Contamination, Keri K. Hall and Jason A. Lyman, Clinical Microbiology Reviews,  p. 788-802, Vol. 19, No. 4. (October 2006).  The journal further explained: “…inadequate skin preparation is thought to be the most common cause of blood culture contamination.” Other medical journals agree:  “Skin microflora represent the most common isolates recovered from contaminated cultures, suggesting that lack of proper skin preparation is the most common cause of contamination.”  See Review of Clinical Trials of Skin Antiseptic Agents used to Reduce Blood Culture Contamination, Anurag Malani, MD; Kim Trimble, MD., Infection Control and Hospital Epidemiology, p. 892 (2007).

The blood sample in question was entirely unreliable due to the failure of medical staff to take the proper precautions.  The crime of DUI has serious consequences, and it stands to reasons that a person may only be convicted of such an offense if the evidence used against him is scientifically reliable.  If fermentation is taking place in a blood sample due to contamination, there is no way to determine what the blood alcohol level was at the time that the sample was actually drawn.  Often times the laboratory staff, or police, or even prosecutors on occasion turn a blind eye to the contamination of the evidence in a court of law.  A person facing a DUI or DWI charge stands alone in a court of law against flawed practices of evidence collection.  It is important for attorneys to assist a defendant to help him through our imperfect criminal justice system.  The problem with the blood collection in this case is not limited to Stevens County.  I have observed similar instances in Okanogan and in Grant County.

One Response to “Problems with DUI blood samples at State Toxicology Lab”

  • Gail Sheppard:

    Curious: Does the same sort of contamination affect the results of drug tests? If a sample is tested one month after it is collected, is this an issue?

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Steve Graham is a criminal defense lawyer, and he splits his time between Spokane and Seattle, Washington. Visit his website by clicking:
Law Office of Steve Graham
1312 North Monroe Street, #140
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(509) 252-9167
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