The Defenses a Lawyer Will Use in a DWI Case

Houston isn’t just a major metropolis — it’s also ranked among the top 10 most fun cities in America. Known for its vibrant nightlife, Texas-themed events, and countless entertainment options, the city offers no shortage of excitement. However, all this fun can come with its share of risks.
One of the most common risks associated with Houston’s nightlife is impaired driving. The legal limit for driving while intoxicated (DWI) in Houston and Texas in general is 0.08% for drivers who are 21 years and older. If you surpass this limit, you risk facing DWI charges, which can even include a jail term.
However, being charged doesn’t automatically mean you are guilty. By hiring the best DWI attorney in Houston, they can challenge the case presented against you by using the following defenses:
Contents
1. Challenging the Reason for the Traffic Stop
Every DWI case begins with a traffic stop, but not all stops are legally valid. Police officers are required to have a valid reason, known as reasonable suspicion, to stop you, such as erratic driving or a broken taillight. They can’t pull you over because of a “hunch.”
If there wasn’t any clear traffic violation or suspicious behavior to justify the stop, any evidence collected, including breath tests, may be inadmissible. This is one of the strongest defenses available.
2. Poorly Administered Field Sobriety Tests
Officers rely on standardized field tests (SFSTs) such as the one-leg stand, walk and turn, or horizontal gaze nystagmus. These tests are voluntary and not considered foolproof since they rely on the police officer’s observation.
Additionally, these tests are only reliable when administered according to strict National Highway Traffic Safety Administration (NHTSA) guidelines. A defense lawyer may challenge whether the officer was properly trained, if the environment was conducive to getting accurate results, or if a medical condition affected the defendant’s ability to perform.
3. Inaccurate Breathalyzer or Blood Test Results
Breathalyzers must be calibrated regularly to maintain accuracy and operated by certified personnel. Failure to do this can compromise the results. Blood tests are also vulnerable to contamination or poor storage, especially if the chain-of-custody procedures are not followed.
Your defense attorney can subpoena maintenance logs or lab records to spot any errors that affect the results.
4. Rising Blood Alcohol Concentration (BAC)
Around 20% of alcohol is absorbed in the stomach. The rest enters your small intestine, where it is absorbed directly into your bloodstream. It can take up to 90 minutes for BAC levels to reach their peak, depending on different factors like carbonation or whether you drank on an empty stomach.
A person’s BAC levels can be under the legal limit while driving but rise at the time when they are tested. A lawyer can argue that the driver was not legally intoxicated when operating a car in cases where the test was administered a little later after the stop.
Conclusion
Other defenses an attorney can use are constitutional violations if you were not read the Miranda rights, the search was unlawful, or you were coerced into a confession. Either way, a strong defense in a DWI case is all about challenging evidence and the burden of proof.