9 Ways to Challenge BAC Test Results in DUI Cases

Injury and Accident Attorneys Serving St. Louis, Nearby Missouri, and Nearby Illinois

Blood alcohol content (BAC) test results are often the cornerstone of DUI cases. Despite the accuracies of these tests, however, it’s not uncommon for these tests to produce unreliable – if not possibly inaccurate – results when mistakes are made at various points during the testing process.

Understanding just what these mistakes can be, as well as how to identify them, can be the key to crafting a strong, effective defense against DUI charges.

Options for Refuting BAC Test Results

How to challenge BAC results in DUI cases
How to challenge BAC results in DUI cases

Whether drivers submitted to breath or blood testing during a DUI stop will affect the possible challenges that can be raised against BAC test results.

For BAC test results associated with breath tests/breathalzyers, it can be possible to throw BAC results into question by arguing that (based on the details of the case):

  1. A non-approved breathalyzer device was used.
  2. The breathalyzer device was not properly calibrated prior to the administration of the breath test.
  3. The officer did not wait at least 20 minutes, observing the driver, before administering the breath test.
  4. The breath test was not properly administered for other reasons.
  5. The DUI suspect had certain medical conditions, such as acid reflux or GERD, that may have resulted in false positives during the testing.

For BAC test results associated with blood tests, possible arguments can include that:

  1. An untrained professional collected the blood samples.
  2. The chain-of-custody for the blood samples was broken (meaning that the samples were mishandled); this could result in sample contamination.
  3. The lab that analyzed the blood samples made mistakes in its analysis or methodology.
  4. The analyzing lab has a record of misinterpreting test results.

Challenging BAC Test Results: More Important Info for the Accused

  • Getting started – It may not always be clear to those accused of DUI just what their best options may be for trying to refute BAC test results. Generally, examining the details of the police report is a good place to start looking for ways to challenge these results. And an experienced lawyer will know what to look for and can advise the accused of their best defense option(s).
  • BAC test refusals – If there were no BAC test results associated with a DUI case because the driver refused this testing during the traffic stop, prosecutors may use the refusal as “evidence” of impairment (likely contending that the testing was refused because the suspect knew (s)he was drunk). In these cases, there can be other ways to challenge prosecutors’ allegations and craft a strong DUI defense case.

Contact a St Louis DUI Lawyer at Brown & Brown Attorneys at Law

If you have been arrested for a drunk driving offense, contact an experienced St Louis DUI injury lawyer at Brown & Brown Attorneys at Law to immediately start defending your rights and protecting your interests. We have a long-standing commitment to serving our clients, and we are experienced at aggressively defending their rights and interests in any setting.

To learn more about how we can help you, call our firm today at 573-333-3333 for our Missouri office or at 618-888-8888 for our Illinois office. You can also email us using the form at the right-hand side of the screen.