By Graham Norris

Every DWI case is built on a foundation of evidence, and that evidence chain begins the moment the officer activates their lights. If the initial traffic stop was not legally justified, then everything that follows—including field sobriety tests and breathalyzer results—may be suppressed and thrown out of court.

Law enforcement cannot pull you over on a mere hunch or suspicion. An officer must have reasonable suspicion—a specific, articulable fact—that a traffic violation or crime has occurred. This is a fundamental protection of your Fourth Amendment rights. If it can be shown that the officer lacked a valid legal reason for the stop, the entire case can be significantly weakened or even dismissed.

Your First Line of Defense: Protecting Your Rights at the Scene

While building a powerful legal defense happens after an arrest, the groundwork for that defense is often laid during the traffic stop itself. Your actions in these critical moments can significantly shape the case against you.

• Politely Exercise Your Right to Remain Silent. You must provide your license, insurance, and registration. Beyond that, you are not required to answer questions. Clearly state, “I am choosing to remain silent and will not answer questions without my attorney.”
• Know That Field Sobriety Tests Are Voluntary. The walk-and-turn, one-leg-stand, and eye test are subjective exercises designed to gather evidence. You have the legal right to politely decline to perform them.
• Understand Chemical Test Consequences. You can refuse a breath or blood test, but this triggers an automatic driver’s license suspension for 180 days. This is a strategic decision with immediate administrative repercussions that should be weighed carefully, especially considering the implications for your ALR hearing.
• Stay Calm and Observant. Make mental notes of the conditions and the officer’s procedure. Your credible account of the event can later challenge the official report.

Deconstructing the Field Sobriety Tests

The walk-and-turn, one-leg-stand, and horizontal gaze nystagmus tests are often presented as scientific proof of impairment. In reality, they are subjective performance evaluations that are highly vulnerable to challenge.

• Environmental Factors: Performing tests on a sloped, uneven, or slippery road surface, in poor lighting, or with distracting passing traffic can throw off your balance and focus.
• Physical and Medical Conditions: Innumerable issues, including back or knee problems, inner ear disorders, neurological conditions, or even normal fatigue, can impact your ability to balance and follow instructions.
• Administrative Errors: The National Highway Traffic Safety Administration (NHTSA) has strict, standardized protocols for administering these tests. Officers frequently deviate from these rules, rendering their observations and conclusions unreliable.

Attacking the Scientific Evidence: Breath and Blood Tests

While a breath or blood test showing a BAC over 0.08 seems like irrefutable evidence, these scientific tests are not infallible. They are complex procedures involving sophisticated machines and human operation, and both are susceptible to significant challenges. Knowing what the Texas Penal Code says about DWI provides crucial context for evaluating the legal standards these tests must meet.

• Challenging Breathalyzer Results: The Intoxilyzer machines used in Texas require meticulous calibration and maintenance to produce accurate results. A strong defense will subpoena the machine’s maintenance and calibration logs to look for irregularities. Furthermore, the officer must continuously observe you for a full 15 minutes before the test. Mouth alcohol from recent burping or certain medical conditions like GERD can create a falsely high reading.
• Scrutinizing the Blood Draw and Analysis: Blood tests are vulnerable at every stage, from the draw to the analysis. We examine whether the phlebotomist used a proper, alcohol-free antiseptic swab. Most importantly, we attack the chain of custody—the documented trail of who handled the blood vial and where it was stored from the moment it was drawn until it was analyzed.

The Rising Blood Alcohol Defense

Alcohol does not instantly absorb into your bloodstream; it takes time. The “rising blood alcohol” defense is based on this scientific principle. It is entirely possible that you were under the legal limit while you were driving, but by the time a blood or breath test was administered at the station—often 45 to 90 minutes later—your BAC had risen to a level over 0.08.

This defense requires a careful reconstruction of your timeline and activities. By working with experienced witnesses who can perform retrograde extrapolation—calculating your BAC backward to the time you were actually driving—we can create a compelling argument that you were not legally impaired while operating the vehicle. These scientific defense strategies are part of a comprehensive approach to how to beat a DWI in Texas.

Secure Your Advocate: Take Control of Your Future Today

Knowing these defenses underscores a critical truth: a DWI charge is a complex legal battle, not a foregone conclusion. Success hinges on having an advocate who knows how to meticulously dismantle the prosecution’s case, point by point.

You don’t have to face this challenge alone. Our entire team is built on putting you first with transparent communication, treating you with respect, and fighting tirelessly as your dedicated protector and partner. Schedule your confidential case evaluation today to begin building your defense with a firm that fights not just for a result, but for you.