If you read the news, you've probably figured out that district attorneys place an extraordinary amount on emphasis on blood test results when it comes to prosecuting cases of driving under the influence. That's not surprising, since Washington law clearly states that a blood alcohol content of .08% or higher constitutes impairment. So you might be forgiven if you think that a blood test which produces BAC results higher than .08 always leads to an automatic DUI conviction.
In reality, that's not the case at all. You see, there are several ways that the blood draw process, sample, and analysis can be flawed. Common errors include:
Improperly collected blood: There's more to the process than just sticking a needle into an arm. The person drawing the blood is often someone with limited training or medical experience. Studies have shown that blood draw errors lead to false positives as high as 50% of the time.
Improperly stored blood: Once the blood is drawn, it can't just be shoved into a bag or a pocket while being transported to the place where it is analyzed. Since the presence of sugar, bacteria, and yeast in the blood can result in fermentation (and a higher alcohol reading), errors are common when the sample isn't stored correctly or promptly.
Improperly tested blood: Finally, the method of testing the blood often assumes the existence of alcohol as opposed to confirming that it's present in the sample in the first place. In addition, forensic labs often report their findings without providing the error rate of their tests – which goes against all scientific protocols.
If a blood sample is found to be compromised for any of these reasons, the court is often obliged to discard the test results as evidence in a DUI trial, which could result in the dismissal of charges or an acquittal. However, only a qualified DUI defense attorney knows what to look for regarding possible mishandling or inadequate testing of drawn blood pursuant to a DUI arrest. So if you're ever detained for or charged with a DUI, be sure to contact a DUI defense lawyer to handle your case.