Blood, Breath and Urine Testing for DWI

Woman's arm on a table with 2 hands holding a needle for a DUI blood draw.

When a police officer pulls you over for suspicion of DUI in Louisiana, you may be asked to submit to a chemical test to check your blood alcohol concentration (BAC) level, especially if you have already failed or refused a field sobriety test.

Like most states, Louisiana analyzes BAC using one of 3 chemical tests: a breath test, a blood test, and a urine test.

If you are driving on a public highway, you have already given consent to a chemical test to determine the alcohol content of your blood by virtue of Louisiana’s implied consent law. According to LA Rev Stat § 32:661, Louisiana DWI law states that refusing such a test will result in either a license suspension or additional penalties if this is not your first refusal.

Call our offices today If you’ve been arrested for driving while intoxicated in Louisiana. Bates and McMillin handles clients throughout the state, and our skilled DUI attorneys have years of experience fighting DWI charges.

Breath Alcohol Test

The most common means of testing a driver’s BAC in Louisiana is a type of breathalyzer known as the Intoxilyzer 9000. The amount of alcohol in your blood is detected when you blow into the device.

Each person’s blood alcohol concentration is impacted by common factors such as gender, weight, consumption rate, and the amount of food in your stomach. Two drinks for a 250 pound male would not produce the same BAC level as a 115 pound woman who consumed the same beverages.

The breathalyzer is not a foolproof machine. Several conditions can impact the accuracy of a driver’s test results, including the following:

  • Recent dental procedures
  • Power surges
  • Cell phones
  • Body temperature
  • Smokeless tobacco
  • Denture adhesives
  • Chemical exposure
  • Diabetes
  • Fever
  • Gastroesophageal reflux disease (GERD)
  • Special diets
  • Disease of the lungs
  • Periodontal (gum) disease
  • Faulty bridge work
  • Airbags (Tyndall Effect)

The Intoxilyzer 9000 may also give an incorrect reading due to mistakes made by the police department or state officials. Errors may be caused by machine malfunctions, improper maintenance and improper training by the arresting officer.

Blood Test

Blood tests are common tests for drivers suspected of driving while intoxicated. Even if you choose to refuse a breathalyzer test, Louisiana allows police officers in some parishes to obtain a search warrant for a mandatory blood test.

If you strongly believe that you are not intoxicated during your arrest, you may request an analysis of your BAC via a blood draw.

If you are denied your request for a DWI blood test or you feel a mistake was made, an experienced DUI defense attorney knows how to challenge the state’s evidence.

Urine Test

The urine test is also commonly associated with drug impaired driving arrests though urine testing is considered the least reliable method of determining blood alcohol content. A police officer may suspect you were driving under the influence of drugs once a breath test rules out alcohol impairment and order a urine test.

A skilled DWI defense attorney can identify any flaws in how a urine test was administered and processed and may be able to challenge its admissibility.

Can the Blood, Breath, or Urine Test Results Be Challenged in Your DUI Case?

Yes! DUI attorneys Robert McMillin and James Bates have the skills and experience necessary to determine if your DUI test results can be challenged.

More at Blood Analysis: Hardly a Gold Standard in DWI Testing

Contact Bates and McMillin today if you believe you were falsely charged with driving while intoxicated due to faulty chemical test results.

Call 985-643-0316 if you were arrested for DWI in any of the following parishes:

Call 504-259-7461 if you were arrested for DWI in any other parish in Louisiana, including: