Written by attorney Elisabeth K. H. Pasqualini

Blood Alcohol Content "BAC" tests- Only "Whole Blood" Tests are Sufficient

By Shaffer & Engle Law Offices, LLC posted in DUI on Friday, June 14, 2013

Only testing on whole blood is sufficient to sustain a DUI conviction


By Attorney Elisabeth K.H. Pasqualini, DUI Attorney, Harrisburg, PA

Since 2013, Pennsylvania has stopped relying upon Blood Alcohol Testing conducting using an intoxilyzer machine. That's the machine that you have to blow into that registers your blood alcohol level. What police departments have now been relying upon is a test of a suspect's whole blood.

What you need to know about a whole blood test:

The general rule for alcohol related DUIs is that only tests performed on whole blood will sustain a conviction under Title 75 Pa.C.S.A. Section 3802 (DUI). Thus, evidence of blood serum, plasma or supernatant testing, without conversion, will not suffice. See e.g., Commonwealth v. Renninger, 452 Pa. Super. 421, 682 A.2d 356 (Pa. Super. 1996); Commonwealth v. Michuck, 454 Pa. Super. 594, 686 A.2d 403 (Pa. Super. 1996); Commonwealth v. Wanner, 413 Pa. Super. 442, 605 A.2d 805, 808 (Pa. Super. 1992); Commonwealth v. Bartolacci, 409 Pa. Super. 456, 598 A.2d 287 (Pa. Super. 1991). The reasoning for this rule rests on the distinction between whole blood and blood serum:

The distinction between whole blood and blood serum is significant. Serum is acquired after a whole blood sample is centrifuged, which separates the blood cells and fibrin, the blood's clotting agent, from the plasma-the clear liquid in the blood serum. When blood serum is tested the results will show a blood alcohol content which can range from between 10 to 20 percent higher than a test performed on whole blood. The reason for this is because the denser components of whole blood, the fibrin and corpuscles, have been separated and removed from the whole blood, leaving the less dense serum upon which the alcohol level test is performed. The value of the blood alcohol content in the serum is then determined. Because the serum is less dense than whole blood, the weight per volume of the alcohol in the serum will be greater than the weight per volume in the whole blood. Thus, an appropriate conversion factor is required to calculate the corresponding alcohol content in the original whole blood sample.Michuck, 686 A.2d at 405-406

Commonwealth v. Hutchins, 2012 PA Super 44, 42 A.3d 302, 309-10 (Pa. Super. 2012).

If you've been charged or arrested for a Driving Under the Influence offense, you need to seek competent legal counsel to guide you through this very serious offense. You can lose your driver's license, job, professional license, and it may even impact your ability to maitain custody of a child.

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