The interesting thing about all the different DWI tests is that all of them have the potential to be inaccurate. This includes urine, blood and Breathalyzer tests.
Even though some tests are more likely to be accurate than others, all of them have the potential to be inaccurate if they are performed incorrectly or under the wrong conditions. For example, a blood test that becomes contaminated may ferment or coagulate in a way that throws off the results. Urine tests that are measuring metabolites or traces of drugs might ping positive despite you being totally sober.
Even a Breathalyzer test can be affected by changes in your body’s chemistry or something as simple as mouthwash. That’s why it’s always important to make sure your attorney looks into the tests and is clear that they were performed correctly under the authorized conditions.
How can DUI blood tests be wrong due to contamination?
While it’s unlikely that blood tests will be wrong because of someone tampering with them, the same is not true of accidental contamination. Contamination can occur if a seal is broken or if the body’s flora gets into the blood as it goes into the test tube.
The bacteria that gets into the tube then has the potential to propagate. If that happens, it may cause the blood to begin to ferment. Fermentation creates alcohols, and those alcohols may make your blood test come back positive despite not being intoxicated.
For this reason, it’s normally a good idea to compare the blood test’s findings to Breathalyzer test results. If more than one test was taken, large differences between the test results may indicate a problem with the test. Other evidence might include someone drawing blood because the first tube clotted unexpectedly, which could indicate a problem with the chemicals in the test tubes used to perform the test.
Defend yourself if you’re accused of a DWI
It is your right to defend yourself against DWI charges. If there may have been an error in testing your blood, then that error should be investigated to help you protect yourself against unfair charges and penalties.