Just because you were arrested for DWI doesn’t mean the state has a slam-dunk case against you. In fact, prosecutors lose DWI cases all the time — and it’s often because their evidence has serious problems that a skilled defense attorney can shine a light on.
The truth is DWI arrests happen fast, often in the middle of the night, with officers making split-second decisions under less-than-ideal conditions. That rush to book suspects creates mistakes, inconsistencies, and constitutional violations that can completely unravel a DWI case before it ever reaches trial.
If you’ve been charged with DWI in Texas, watch for these signs that the prosecution’s case against you might be weaker than you think:
- No probable cause for the traffic stop
- Field sobriety tests administered incorrectly
- Breathalyzer equipment wasn’t properly calibrated or maintained
- Blood test samples were mishandled or contaminated
- Video footage contradicts the officer’s report
- Medical conditions that could explain your “impairment”
- Missing or incomplete police reports
Don’t assume your DWI charge is unbeatable just because you were arrested. Mark Thiessen at Thiessen Law Firm has earned 140+ Not Guilty verdicts and 1000+ dismissals in DWI cases by finding and exposing exactly these kinds of weaknesses in the state’s evidence.
Your future is worth fighting for. Call Thiessen Law Firm today at (713) 864-9000 or contact us online to discuss your case and start building your defense.
1. No probable cause for the traffic stop
In Texas, police officers can’t just pull you over on a whim — they need reasonable suspicion that you’ve committed a traffic violation or that criminal activity is taking place. This is one of the most common signs that a criminal case is weak, and it’s often one of the first things an experienced attorney will examine.
If the officer can’t clearly articulate what traffic law you violated or what suspicious behavior justified the stop, everything that happened afterward — including field sobriety tests, breathalyzer results, and your arrest — could be thrown out as “fruit of the poisonous tree.”
Maybe the officer claims you were weaving, but dashcam footage shows you driving normally. Or maybe they stopped you for a burned-out license plate light that was actually working fine. These seemingly small details can completely destroy the prosecution’s case.
2. Field sobriety tests administered incorrectly
Field sobriety tests in Texas are supposed to follow strict, standardized procedures developed by the National Highway Traffic Safety Administration (NHTSA). When officers deviate from these protocols — even slightly — the results may become unreliable and inadmissible in court.
Common mistakes include:
- Giving instructions incorrectly
- Conducting tests on uneven surfaces
- Failing to account for weather conditions
- Not properly demonstrating the tests before asking you to perform them
Officers are also supposed to look for specific “clues” of impairment during each test, and if they can’t identify those clues correctly in their report, it raises serious questions about their training and the validity of your arrest. A skilled defense attorney can tear apart improperly administered field sobriety tests and use them as evidence of a weak DWI case.
3. Breathalyzer equipment wasn’t properly calibrated or maintained
Breathalyzer machines aren’t infallible — they’re complex devices that require regular calibration, maintenance, and proper operation to produce accurate results. DWI law in Texas requires law enforcement agencies to follow strict maintenance and calibration schedules for these machines, and when they don’t, the results can’t be trusted.
Defense attorneys routinely request maintenance and calibration records for the specific breathalyzer used in your case. If those records show missed calibrations, improper maintenance, or that the machine was due for servicing, the breath test results may be suppressed.
Additionally, if the officer operating the machine wasn’t properly trained or didn’t follow the required observation period before administering the test, those results could be challenged and potentially excluded from evidence.
4. Blood test samples were mishandled or contaminated
Blood tests are generally considered more accurate than breath tests, but they’re also more vulnerable to human error and contamination. From the moment your blood is drawn to when it’s analyzed in a lab, there are dozens of opportunities for mistakes that can compromise the results.
Fighting DWIs in Texas often involves scrutinizing the blood sample chain of custody. Was the sample properly labeled? Was it stored at the correct temperature? Did the lab follow proper testing protocols? Was the blood drawn by a qualified professional using a sterile technique?
If the phlebotomist used an alcohol-based swab to clean your arm before the blood draw, that alone could artificially inflate your BAC reading. Any break in the chain of custody or deviation from proper procedures can render the blood test results unreliable.
Continue reading: How to fight a DWI in Texas
5. Video footage contradicts the officer’s report
Dashcam and bodycam footage can be your best friend in fighting a DWI charge. Officers often write reports that paint you in the worst possible light, describing “slurred speech,” “bloodshot eyes,” and “inability to follow instructions.” But when video footage shows something completely different, it can evaporate the prosecution’s case overnight.
Maybe the video shows you speaking clearly and coherently during your interaction with the officer. Perhaps it reveals that you actually performed the field sobriety tests better than the officer’s report suggests. Or it might show that you weren’t stumbling or having trouble with balance.
Houston DWI lawyers know that video evidence is objective and powerful — and when it contradicts the officer’s subjective observations, juries tend to believe what they see with their own eyes rather than what they read in a police report.
6. Medical conditions that could explain your “impairment”
Not everyone who appears “impaired” is actually intoxicated. Numerous medical conditions can mimic the signs of intoxication, and officers who aren’t medical professionals often can’t tell the difference. This is especially important if you’re facing your first DWI in Texas and have a legitimate medical explanation for your behavior.
Conditions like diabetes (which can cause breath to smell like alcohol and affect balance), neurological disorders, inner ear problems, injuries, and even anxiety can all produce symptoms that look like intoxication to an untrained observer.
If you have a medical condition that explains why you failed field sobriety tests or appeared impaired, medical records and expert testimony can be powerful tools in your defense. Even for serious charges like intoxication manslaughter, medical evidence showing that symptoms were misinterpreted as intoxication can be case-changing.
7. Missing or incomplete police reports
Police reports are supposed to document every important detail of your DWI stop and arrest — but when officers cut corners or fail to properly document their investigation, it creates gaps that defense attorneys can exploit. Missing information isn’t just sloppy paperwork; it can be a sign that the officer’s case against you doesn’t hold up.
Common problems include:
- Missing dashcam or bodycam footage that the officer claims “malfunctioned”
- Incomplete documentation of field sobriety tests
- Failure to note important observations
- Inconsistencies between different reports filed by multiple officers on the scene
When key pieces of evidence are missing or reports don’t match up, it raises reasonable doubt about the entire arrest. If the state can’t produce complete documentation of what happened, how can they prove beyond a reasonable doubt that you were intoxicated?
Weak DWI cases — FAQs
What are the odds of getting dismissed for a DWI in Texas?
Wondering how to get a DWI dismissed? Dismissals typically involve identifying constitutional violations, procedural errors, or problems with the state’s evidence — exactly the kind of work an experienced DWI attorney does. While there’s no guaranteed dismissal rate, having a skilled lawyer who knows what to look for dramatically improves your chances compared to going it alone.
How do you know if your criminal case is weak?
The case against you is likely weak if there are problems with how evidence was collected, if police violated your constitutional rights during the investigation, or if the prosecution’s evidence is based on unreliable witness testimony or faulty testing procedures. Common red flags include missing documentation, video footage that contradicts police reports, improper search and seizure, or technical errors in how tests were administered.
What is considered weak evidence?
In DWI cases specifically, weak evidence often includes breathalyzer results from poorly maintained machines, field sobriety tests administered incorrectly, or blood samples with broken chains of custody. The weaker the evidence against you, the harder it is for prosecutors to prove their case beyond a reasonable doubt.
Don’t let a weak DWI case turn into a conviction — call Thiessen Law Firm today
A DWI arrest isn’t the same thing as a DWI conviction — and the differences between those two outcomes often come down to whether you have an attorney who knows how to spot and bring to light weaknesses in the state’s case.
At Thiessen Law Firm, we don’t accept the prosecution’s version of events at face value. We dig into every detail of your arrest, from the initial traffic stop to the final blood test results, looking for the cracks that can bring down their entire case. Mark Thiessen and our team have gotten thousands of DWI cases dismissed or reduced by doing exactly this kind of aggressive, detailed defense work.
Your DWI case might be much weaker than it appears — but you’ll never know unless you have an experienced attorney review the evidence and fight for you. Whether it’s your first DWI or you’re searching for an intoxication manslaughter law firm, don’t plead guilty to charges that won’t hold up in court.
Call Thiessen Law Firm today at (713) 864-9000 or contact us online to schedule a consultation.
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