Blood Evidence

Blood Evidence2023-08-22T19:17:23+00:00

Many of my DUI clients most significant concern is their “blood alcohol content” (“BAC”). I get questions like, “If my BAC was reported at 0.21, that means I lose, right?” The short answer to this question is not necessarily. Your alleged BAC is just the beginning of the analysis.

Your blood was analyzed by a machine. The machine that was used to analyze your blood has various components. These components have to be configured properly and thereafter confirmed to be working properly (“calibration”). Most importantly, the machine that was used to analyze your blood was operated by a person. Ultimately, the conclusions that: (1) alcohol (or a prohibited substance) was in fact in your blood; and (2) that your BAC (or prohibited level content) was at a specific level hinge on the method the operator utilized to analyze your blood and his or hers’ subsequent interpretation of the data generated by his or her method.

The machine that was used to analyze your blood is not a simple machine that you simply insert blood into to obtain a reading “alcohol present at 0.21%.” Your blood was analyzed by a scientific process known as “chromatography.” The specific machine that was used to analyze your blood depended on what the machine operator was instructed to look for. If the operator was instructed to analyze your blood for its alcohol content (ethanol), your blood was analyzed by a “Head-Space Gas Chromatograph with a Flame Ionization Detector” (commonly abbreviated as “HS-GC-FID”). If drugs were suspected in your case, than it is very likely that your blood was also analyzed by a “Liquid Chromatograph with a Mass Spectrometer Detector” (“LC-MS”).

“Chromatography” is the process of separating the ethanol (alcohol) from the other compounds in your blood so the amount can then be quantified (how much?). Think of it like this, if you cannot differentiate between the ethanol (alcohol) and glucose (or other compounds) in a blood sample, you cannot determine how much ethanol (alcohol) is present in the blood. After the ethanol (alcohol) is separated from the other compounds in your blood, the detector in the machine (FID) then determines the amount. The results of the analysis are then printed on a report known as a “chromatogram.” The operator then reads the chromatogram, makes necessary conversions and signs a toxicology report declaring that he or she “analyzed” your blood and determined that your BAC was 0.21.

It is important that you hire an attorney that is educated and trained on chromatography. Your attorney needs to be able to request the appropriate data and thereafter be able to review it and determine whether your specific test was performed properly. Mr. Hayes has been educated and trained on the theory and operation of forensic chromatography by Professor Emeritus Harold McNair. Professor McNair was the first person to receive a Ph.D. in chromatography in the United States and founded two of the companies that manufacture over 80% of the world’s chromatographs. Mr. Hayes has been educated and trained on chromatography by the same instructors that train and educate the DEA, FDA, DOD, ATF and FBI. If you would like the blood evidence in your case thoroughly reviewed, contact the DUI Lawyers of Las Vegas to schedule a free and confidential consultation.