Open Accessibility Menu
  • TBLS Board Certified in Criminal Law

    Mark Thiessen is honored to be selected to this prestigious Criminal Law certification which distinguishes only a few attorneys as specialists.

  • Top 100 Super Lawyers in Houston - 2017-2018

    Our firm had been selectively chosen during Super Lawyers’ rigorous evaluation.

  • DUIDLA - Board Certified

    Board certification by the DUI Defense Lawyers Association (DUIDLA) is only earned by those who score a passing grade or higher on the Board Certification Exam. At Brockmeyer Law Offices, our DUIDLA Board Certification demonstrates an exhaustive, in-

  • ACS/CHAL Lawyer Scientist

    An ACS-CHAL Forensic Lawyer-Scientist is someone who used validated, legitimate science to benefit others in their pursuit of justice.

  • National College for DUI Defense

    We, along with our fellow College members, are some of the most experienced DUI defense lawyers in the nation. Only attorneys who have consistently demonstrated exceptional skill in handling DUI matters are appointed to the College.

  • The National Trial Lawyers Top 100

    We are among the nation’s most elite trial advocates, and our membership with National Trial Lawyers: Top 100 allows us to become even better through continuing legal education (CLE) programs.

  • Super Lawyers

    Super Lawyers designations are reserved only for attorneys who display a commitment to excellent client experiences and consistently positive results in court, as determined during objective review by third parties, nomination by established peers.

  • AV Preeminent Rated by Martindale-Hubbell

    AV Preeminent Ratings are awarded based on outstanding peer reviews and client testimonials. This is the highest peer rating standard in the legal industry.

  • Avvo 10.0

    A perfect score from Avvo is calculated by evaluating a firm’s experience, proven skill, track record, and client reviews.

  • Texas Criminal Defense Lawyers Association (TCDLA)

    As members of the TCDLA, we are proud to be regular participants in the Association’s educational programs.

Felony DWI Lawyer in Houston

Trust Proven Texas Trial Attorneys. Call (713) 999-3959

Being charged with any DWI offense can put a lot on the line, but if that offense meets criteria outlined under Texas law for felony-level allegations, defendants often face severe and life-altering penalties. When it comes to your freedom and future, subpar legal representation simply won’t cut it.

We've achieved 100+ not guilty verdicts for our clients!

Thiessen Law Firm is comprised of proven and nationally recognized Houston DWI defense attorneys with demonstrated success in cases involving misdemeanor and felony DWI. Whether you or your loved one have been charged with a felony DWI in connection to a singular offense involving driver impairment and a motor vehicle accident, or as a result of accumulating too many DWI convictions on your record, our firm is poised and prepared to provide the aggressive and knowledgeable representation you need.

Why Thiessen Law Firm?

  • Led by a Board Certified Criminal / DUI Specialist – Founding Attorney Mark Thiessen is Board Certified in Criminal Law by the Texas Board of Legal Specialization, and in DUI Defense by the DUI Defense Lawyers Association.
  • A Proven Record of Results – Our attorneys have secured more than 100 "not guilty" verdicts for our clients, as well as a number of positive resolutions in all types of DWI and criminal cases.
  • Step-by-Step Guidance – From assistance with bail bonds to independent investigations, customized defense strategies, and the plea negotiation or trial process, we guide clients through every step of their legal journey with a firm stance on protecting their rights.
  • True Fighters – Attorney Mark Thiessen and our legal team are passionate about fighting for the rights, freedoms, and futures of our clients – both inside and outside of the courtroom.

Call (713) 999-3959or contact us online for a free and confidential consultation. Thiessen Law Firm is available 24/7 to help residents throughout Houston and the surrounding areas of Texas.

Felony DWI in Texas: A Life-Threatening Allegation

Make no mistake about it, felony DWI charges are serious and potentially life-altering allegations. From threatening one’s personal and professional reputation to creating exposure to a loss of civil rights, license suspension or revocation, court supervision, substantial monetary penalties, and significant terms of imprisonment, felony DWI charges mean there’s a lot you can lose.

Under Texas law, driving while intoxicated or under the influence of drugs is typically a misdemeanor offense. However, there are certain circumstances which can elevate these charges to felonies.

DWI can be charged as a felony in Texas if the following applies:

  • A Third DWI– If you have two or more DWI convictions on your record, you can potentially be charged with a felony DWI. As a third-degree felony, this charge is punishable by a 2-year driver’s license revocation, fines and fees amounting to $10,000, court-ordered community service, and up to 10 years in a Texas state prison.
  • Accidents Resulting in Injury – Motorists suspected of driving while intoxicated or under the influence of drugs may be hit with felony DWI charges if they are also suspected of causing accidents that resulted in any person suffering serious injuries. In addition to hundreds of hours of court-mandated community service, up to $10,000 in fines and fees, and driver’s license suspension/revocation, being convicted of this third-degree felony (known as “intoxication assault”) can subject defendants to up to 10 years in state prison. The law notes victims must suffer “serious bodily injury” as a proximate cause of a defendant’s intoxication for prosecutors to pursue this charge.
  • Accidents Resulting in Death – There are few circumstances as serious as fatal accidents, which is why felony DWI allegations stemming from wrecks where a victim is killed make for the most serious DWI / DUI charge a person can face in Texas. Known as “intoxication manslaughter,” this second-degree felony offense is punishable by up to 20 years in state prison.
  • DWI with Child Passenger – Being arrested under suspicion of driving while intoxicated or under the influence of drugs with a child passenger in the vehicle is a state jail felony. As such, it’s punishable by a minimum of 180 days in jail and up to 2 years in a state jail facility. Under Texas law, a “child passenger” is any minor under the age of 15.

You only have 15 days to
save your license!

If you've been arrested for a DWI or DUI in the state of Texas, you are facing two cases against you. The first one is the criminal case by the state of Texas, and the other is by the Texas Department of Public Safety to suspend your license.

Learn More

Felony DWI Defense: Exploring Tailored Strategies

Relying on a public defender or a private defense attorney who lacks considerable insight into Texas DWI laws and how these cases pan out can be a critical mistake with tremendous consequences. Over the years, clients across Houston and beyond have come to trust Thiessen Law Firm because we practice what we preach – hard-hitting DWI defense strategies based on extensive experience, the insight and specializations of our attorneys, and the individual aspects of our clients’ unique cases.

Though every case is different, and your defense strategies dependent on the unique facts of your case, there are some general issues we often explore as we guide clients through the legal process and toward the most favorable resolution possible. Examples include:

  • Investigating law enforcement protocol, which can include independent investigations into whether arresting officers complied with the special rules and procedures by which they’re bound, had sufficient reasonable suspicion / probable cause to pull drivers over or conduct a search and seizure, and whether they infringed upon our clients’ Constitutional rights. These investigations can prove critical to having certain evidence or findings dismissed, which in turn could compromise prosecutors’ cases and result in dismissals or substantial reductions.
  • Challenging the evidence, which can vary from case to case. From digging into law enforcement procedures to meticulously scrutinizing video, police reports, testimony, and various impairment / chemical tests, there’s a lot of evidence to review, but limited opportunity to effectively challenge that evidence. Experienced DWI defense attorneys like those at Thiessen Law Firm know how to dissect evidentiary documents, apply their knowledge of Rules of Evidence and case law, and use their findings to challenge the government’s case. Often, that requires a strong working knowledge of multiple areas of science, from anatomy and physiology to toxicology, chemistry, computer science, and more.
  • Challenging the tests and the science, which in addition to challenging the results of Field Sobriety Tests (which aren’t mandatory) and preliminary breath / PAS tests administered at the scene (which also aren’t mandatory), also means challenging any evidence obtained by chemical testing of a suspect’s breath, blood, or urine at a local hospital, jail, or law enforcement facility. Founding Attorney Mark Thiessen is recognized as an ACS CHAL Lawyer-Scientist for his understanding of the science and technology behind DWI breath and blood testing and substance impairment. He frequently shares this insight with fellow DUI / DWI practitioners as a legal educator, author, and lecturer, and uses it for the benefit of clients to challenge breath and blood test results when it matters most – during their cases.
  • Negotiated resolutions, which necessitate more than superficial “bargaining” with prosecutors, and require leverage obtained by skilled and resourceful attorneys who are able to compel the government into reaching favorable negotiated plea agreements that reduce charges and / or penalties, or obtain some other desired result unique to a client’s case and future.
  • DWI trials, which by no means happen regularly or with any guaranteed results. As trial-tested attorneys, we help clients explore their right to trial, as well as any available means for weaving a thread of doubt that discredits prosecutors and dismantles the government’s case. Few lawyers win DWI trials with the types of results or with the regularity as our firm does, and few have the willingness to even take cases with merit to the courtroom simply because they make for difficult and daunting proceedings.

Discuss Your Case & Options During a FREE Consultation: (713) 999-3959

Our entire team at the Thiessen Law Firm takes pride in having cultivated a reputation as skilled, committed, and aggressive advocates for those charged with serious crimes – and for the many positive results we’ve secured on our clients’ behalves. If you have a felony DWI case to discuss, we encourage you to reach out as soon as possible – these charges demand a front-footed approach, and the attention of highly experienced defense attorneys. Our firm is available 24/7 to help.

Call (713) 999-3959 or contact our firm online to request a free review of your case.

Free Consultation

Please call or complete the form below and we will respond back as soon as possible.

713.864.9000 Get Started Now Available 24 hours a day, 7 days a week.
  • "The BEST Attorney in Harris County!!"
  • "If You Want a GREAT Lawyer, Mark Thiessen is Your Man"
  • "The Best Lawyer in the Industry"
  • "Excellent Attorney to Have Represent You"
  • "Fantastic Lawyer!"
  • "Best DWI Lawyer out there!"
  • "Mark Thiessen Has The “IT” Factor"
  • "Amazing, Reliable and Superb Attorney! The Great Mark Deserves 100% Marks"
  • "You Cannot Compare Anybody with Mr.Mark!"
  • "Mark Eres Mi Hombre Que Luchó Por Mi Libertad y Justicia!!!"
  • "When you really need somebody to defend you I recommend you go hire Mark Thiessen."
Read Our Testimonials


Not Guilty Verdicts
  • .171 Breath Test - Not Guilty
  • 0.119 Blood Test - Not Guilty
  • 0.158 Blood Test - Not Guilty
  • 0.146 Breath Test - Not Guilty
  • 0.176 Breath Test - Not Guilty
  • 0.184 Blood Test - Not Guilty
  • 0.10 Breath Test - Not Guilty
  • 0.194 Blood Test - Not Guilty
  • 0.16 Breath Test - Not Guilty
  • 0.199 Blood Test - Not Guilty
  • 0.140 Breath Test - Not Guilty
  • 0.098 Blood Test - Not Guilty
  • 0.127 Breath Test - Not Guilty
  • Not Guilty - Not Guilty
  • 0.144 Breath Test - Not Guilty
  • 0.172 Breath Test - Not Guilty
  • .24 Breath Test - Not Guilty
  • Intoxicated Assault - Dismissed
  • .17 Breath Test - Dismissed
  • .22 Blood Test - Dismissed Mid Trial
  • .16 Breath Test - Dismissed
  • 0.161 Blood Test - Not Guilty
  • No Test, No Accident - Not Guilty
  • .16 Blood Test - Not Guilty
  • .21 Blood Test - Not Guilty
  • 0.226 Blood Test - Not Guilty
  • Intoxicated Manslaughter - Not Guilty
  • DWI - Not Guilty
  • DWI Breath Test .10 - Not Guilty
  • 0.138 Blood Test - Not Guilty
See Our Results
Request Your Free eBook

A Texas DWI Can Cost You $15,000

Get the DWI facts no Texan should drive without, including:
  • 3 rights you can exercise when you get pulled over
  • How to save your license from suspension
  • Why you should refuse any roadside tests
  • What to say during your booking
This isn't a valid email address.
Please enter your email address.

Meet Our Legal Team

As one of Houston’s most distinguished criminal defense firms, Thiessen Law Firm emphasizes quality over quantity. We will get to know your case better than anyone and will utilize every tool at our disposal to secure the results you need. We are dedicated to your needs – 24 hours a day, 7 days a week. As soon as you hire us, you will receive the direct contact information on everyone on your case.

Meet Our Team
Prev Next

Recent News & Updates

  • Aug 4, 2018 by: Mark Thiessen

    Can You Buy a Gun with a DWI Charge in Texas?

    Read More
  • Jan 22, 2018 by: Mark Thiessen

    How the Open Container Law Works in Texas

    Read More
  • Sep 18, 2017 by: Mark Thiessen

    How an Illegal Traffic Stop by Police can Impact Your Criminal Case

    Read More

Request Your Free Consultation

Fill out the form below or call (713) 999-3959 and we'll get back to you shortly.

  • Please enter your First Name.
  • Please enter your Last Name.
  • This isn't a valid phone number.
    Please enter your phone number.
    You entered an invalid number.
  • This isn't a valid email address.
    Please enter your email address.
  • Please make a selection.
  • Please enter a message.