Blood Test

Depending on the law in the state in which DUI/DWI stop occurs, the driver may be offered to have Blood Alcohol Content (BAC) measured by a blood test, as opposed to a breathalyzer. Guidelines in the statute will describe how the test must be administered, transported, preserved, analyzed, etc. Although blood testing is generally considered the most accurate means of testing Blood Alcohol Content, many things can go wrong, including: an alcohol swab that was used to sterilize the blood draw area can contaminate the specimen; mixing the preservative and anti-coagulant in the blood sample can lead to the sample fermenting and being useless and samples get lost and/or confused with other samples (i.e., the chain of custody can be difficult for the Prosecution to prove). See also, DUI/DWI, Blood Alcohol Content, Breathalyzer.