While the breath test is supposed to measure Blood Alcohol Content (BAC), it doesn’t give the same reading as a blood test. In reality, your breath test could be substantially different from your blood test. But why? Well, it’s because the two tests are actually measuring different things. The alcohol content of the alveolar air is being measured in a breath test. The standard partition ratio of 2,100 to 1 is then applied to estimate your blood alcohol level. But a blood test will measure the percentage of alcohol in whole blood. As a result, the two tests could vary, assuming your partition ratio is not exactly 2,100:1.
The state typically relies on blood test evidence in North Carolina DWI cases involving accidents. The circumstances of the accident itself are often deemed enough to establish reasonable suspicion of impairment, and so field sobriety tests are unnecessary; and when a driver is unable to take a breath test, the State will administer a blood test. To learn more, schedule your consultation with a skilled DWI defense attorney.
