Houston · Harris County · Galveston · Fort Bend · Federal — Southern District of TexasHouston · Harris County · Galveston

Almost every DWI begins with a traffic stop — and if that stop was unlawful, the whole case can fall apart. The Constitution requires an officer to have reasonable suspicion to stop you and probable cause to arrest you. When those requirements aren't met, a motion to suppress can throw out the field sobriety tests and the breath or blood results — often leaving the State with nothing to prove its case.

If you or a loved one is facing a DWI in Houston, Harris County, or Galveston, Brian Foley and Luis Baez — former prosecutors — can help.

The Legal Standards

StageWhat the officer needs
The stopReasonable suspicion — specific, articulable facts, not a hunch
The detentionSuspicion that justifies the scope and length of the stop
The arrestProbable cause to believe you were driving while intoxicated
A blood drawConsent or a valid warrant supported by probable cause

If the State fails at any of these stages, the evidence obtained afterward may be suppressed under the exclusionary rule.

Common Problems We Look For

  • No real traffic violation. Stops based on a vague, mistaken, or non-existent violation.
  • Prolonged or expanded stops. Detaining you longer than the stop's purpose allows, or turning a minor stop into a DWI investigation without new suspicion.
  • Mistakes of law. Stops based on conduct that isn't actually illegal.
  • Unreliable "signs of intoxication." Odor, "glassy eyes," and similar boilerplate frequently don't hold up against the video.
  • Defective blood warrants. Affidavits lacking probable cause or proper procedure.
The video usually tells the real story

Dash-cam and body-cam footage often shows normal driving, misadministered field sobriety tests, or a client who looks and sounds sober — contradicting the offense report. We obtain and scrutinize all of it.

How Suppression Wins Cases

When we identify a constitutional problem, we file a motion to suppress and litigate it before trial. If the judge agrees the stop, arrest, or search was unlawful, the tainted evidence is excluded. Because DWI cases depend on that evidence, a successful motion frequently results in a dismissal or a favorable resolution. Even an unsuccessful motion can expose weaknesses that improve your negotiating position.

Related Pages

Why HCDA

Brian Foley is Board Certified in Criminal Law, and both he and Luis Baez are former prosecutors who know how DWI stops are supposed to be conducted — and how to challenge them when they aren't. If you or a loved one is facing a DWI in Houston, Harris County, or Galveston, contact Houston Criminal Defense Attorneys PLLC for a free, confidential consultation. Call or text (713) 703-1718.

Frequently Asked Questions


What does an officer need to pull me over for DWI in Texas?
An officer needs reasonable suspicion — specific, articulable facts suggesting a traffic violation or criminal activity — to make a stop. A hunch is not enough. If the stop was not supported by reasonable suspicion, everything the officer discovered afterward, including field sobriety tests and breath or blood results, can be suppressed.
What is a motion to suppress in a DWI case?
A motion to suppress asks the court to exclude evidence that was obtained in violation of your constitutional rights — for example, evidence from an unlawful stop, detention, arrest, or search. If the motion is granted, the State often loses the evidence it needs to prove the case, which can lead to a dismissal.
Can a DWI be dismissed because of a bad traffic stop?
Yes. An unlawful stop is one of the most powerful defenses in a DWI case. If the court finds the officer lacked reasonable suspicion to stop you, or probable cause to arrest, the resulting evidence is thrown out — and without breath, blood, or field-sobriety evidence, the State frequently cannot proceed.
What are common problems with DWI stops?
Common issues include stops based on a vague or non-existent traffic violation, prolonging the stop beyond its lawful purpose, expanding the investigation without new suspicion, mistakes about the law, and unreliable claims about 'signs of intoxication.' In-car and body-camera video often contradicts the officer's report.
Does video help in a DWI stop case?
Enormously. Dash-cam and body-cam footage frequently show driving that was fine, field sobriety instructions that were given incorrectly, or a client who looked and sounded sober — directly contradicting the offense report. We obtain and analyze all video in every DWI case.

Speak With a Houston Criminal Defense Attorney Today


Free, confidential consultation with Board Certified criminal defense attorneys and former prosecutors.

(713) 703-1718