Problems That Can Occur with Chemical DUI Tests

forensic toxicology working group members November 18, 2015 Forensic Toxicology

Article overview: This article explains Problems That Can Occur with Chemical DUI Tests and the scientific, legal or practical evidence readers should understand.

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Get Chemical DUI Test Help From an Expert Witness In a court of law, the judge and jury can be influenced by the testimony of an expert witness. An expert witness will provide a testimony to your innocence. This is a person who has studied extensively, has the relevant training, skill or life experience on a particular subject in order to become the best in his or her respective field. Chemical tests analyze your breath, urine or blood to determine your blood alcohol concentration level. If your blood alcohol concentration level is above 0.8% you are considered to be under the influence of alcohol and will be charged with a DUI if found driving a motor vehicle in this state. In terms of forensic toxicology however, there are numerous problems that can occur with chemical tests, such as negligence on behalf of an overworked police precinct lab or hospital staff or even a fault in the chemical test device itself. There are multiple external influences that question the accuracy and legitimacy of chemical tests. Every test is subject to error by means of a range of variables that may influence the results of a chemical test. Some examples of this include:

Blood samples that can be tainted by the certain types of medication that you may be taking. If you have a bad cough and are prescribed a cough syrup that contains an alcoholic component or even ginseng, your blood sample will show an excessively high alcohol level, simply because of the medication you were taking.
Blood samples may also be contaminated or, if left unpreserved, it can ferment and provide inaccurate or false results.
Urine samples can be taken a few hours too late to accurately determine your blood alcohol concentration from the time you were originally pulled over.
Breathalyzer tests are also often used, but respiratory problems or irregular breathing patterns can affect the accuracy of these.

Regardless of the overabundance of factors that could taint sample results or lead to inaccurate blood alcohol concentration results, chemical tests are still more frequently used that field techniques (walking in a straight line, for example). A forensic toxicology expert witness will be able to aid you in disproving faulty field or chemical tests. If an expert witness is called upon, he or she may dispute the results of a Breathalyzer test by performing tests on the machinery used to determine if it has been properly maintained or if it is faulty. By consenting to a blood test, you will have two vials of blood drawn; one for the state and one to be used by your defense and this will be tested in an independent laboratory. This will provide the exact blood alcohol concentration level instead of an estimated amount. Blood tests can be retested (unlike breathalyzer tests) and the results of a blood test are ironclad. Forensic toxicologists, such as Okorie Okorocha, are the best in their field at disproving faulty test results and providing a reliable solid defense for their clients.

Related reading: For related context, read Advantages and Disadvantages of Drug Testing, Comparing Gas Chromatography with Enzymatic Assay, Telling History with Hair. Browse the Forensic Toxicology topic hub.