DWI is one of the most common arrests in Texas, but nonetheless carry potentially severe penalties. In addition to the risk of going to jail for up to six months for a first offense, a person convicted of DWI faces license suspensions, surcharges from the Texas Department of Public Safety, and other potentially burdensome restrictions on his or her driving.

The evidence the State generally uses to prove that someone was intoxicated are field sobriety tests, breath tests, blood tests, “Drug Recognition Expert” tests, and occasionally, urine tests. Hiring an attorney who understands how these tests are performed and the errors that may be made in the administration of these tests is essential to obtaining the best possible outcome in a DWI prosecution. Houston-based DWI Attorney David Nachtigall has tried cases to juries involving all forms of forensic evidence used to prosecute DWI cases, and understands how DWI cases are investigated, where law enforcement can make mistakes, and how a DWI can be defended. Contact our firm to discuss your case with a Houston DWI lawyer, and read below to learn more about the DWI process.

Administrative License Revocation (ALR)

A person charged with DWI who fails or refuses to take a breath or blood test is subject to a driver’s license suspension. The suspension is automatic, unless a Administrative License Revocation (ALR) hearing is requested within 15 days of receiving notice of the suspension. In an ALR hearing for drivers over the age of 21, the State must prove that there was:

  • reasonable suspicion or probable cause for the officer to stop and arrest the driver; and
  • probable cause for the officer to believe the driver was intoxicated; and
  • that the driver was offered the opportunity to provide a specimen of breath or blood and refused; or
  • the driver has an breath of blood alcohol concentration of 0.08 or greater while driving or in actual physical control of a motor vehicle in a public place.

The ALR phase can also be an opportunity to obtain evidence to defend a DWI case, and failure to request a hearing on time can waive that opportunity. Hiring a DWI lawyer before an ALR hearing may allow you to save your license or obtain valuable evidence the State intends to use against you in your DWI case.

Field Sobriety Tests

A person accused of DWI is usually offered the opportunity to perform field sobriety tests. These tests include the horizontal gaze nystagmus (HGN) test, the walk-and-turn test, the one-legged-stand test. Another field sobriety test that is not standardized, but commonly used, is the Rhomberg test. Police officers look for “clues” on these tests to determine whether a person passes or fail the field sobriety tests. These “clues” include stepping off of a line, dropping one’s leg, etc. Based on the results of the field sobriety tests and other observations the officer makes, you may be arrested, brought down to the police station and given the opportunity to take a breath test.

Portable Breath Tests

An officer may use a portable breath test machine as part of his reason to arrest you, but the results of portable breath tests are usually not admissible in a trial as evidence of intoxication.

The Breath Test

The breath test is a common evidentiary tool used by law enforcement in DWI investigations. The machine most commonly used in Texas to measure breath alcohol content is the Intoxylizer 5000. It is a machine that requires proper maintenance and calibration in order to function correctly. If the government can prove that a person’s breath alcohol content was .08 or greater at the time of driving, he or she is considered intoxicated under Texas law. Failure to properly maintain, calibrate, and operate the breath testing machine means that it can deliver inaccurate results and lead to false charging decisions on the part of law enforcement.

Blood Tests

Because of the institution of “no refusal” policies by some District Attorney’s Offices, blood tests are increasingly common in the prosecution of DWI cases. Police departments are required to employ nurses or other qualified individuals to draw the blood of DWI suspects who either consent to a blood draw or are forced to provide blood pursuant to a search warrant. If a person’s blood alcohol content at the time of driving is a .08 or greater, that person is considered intoxicated under Texas law. Improperly qualified individuals drawing blood, failure to follow procedure, and other factors related to the storage and testing of blood may contaminate a blood sample and lead to false results and unlawful convictions.

No Refusal

District and County Attorney’s offices throughout Texas have implemented “no refusal” programs. This means that if a person is suspected of DWI and refuses to submit to a breath test, the arresting officer may immediately seek a search warrant to take a blood sample. Prosecutors work 24-hours a day in shifts to draft warrants for an arrested person’s blood. Once the warrant has been approved by a judge, an nurse or other person employed by law enforcement draws a blood sample. Errors in way a search warrant is prepared or drafted, and errors related to the collection and testing of blood may provide opportunities for the effective defense of a DWI charge. In Houston and Harris County, the District Attorney’s Office is no longer accepting charges without breath or blood evidence. Hiring an experienced DWI attorney who understands this evidence is crucial to an effective defense.

Multiple DWI Convictions

Repeated DWI convictions may change the punishment one faces considerably. Under Texas law:

  • A first DWI conviction is a Class B misdemeanor, punishable by up to six months in jail and a $2,000 fine
  • A second DWI conviction is a Class A misdemeanor, punishable by up to one year in jail and $4,000 fine
  • A third or more DWI conviction is a third degree felony, punishable by up to ten years in prison and a $10,000 fine

DWI Involving Children, Injury, or Death

The District Attorney’s Office and our community take these crimes very seriously. Some District Attorney’s Offices have entire divisions devoted to the prosecution of those individuals charged with DWI offenses involving serious injury or death.

  • A DWI with a child passenger is a state jail felony punishable by six months two years in a state jail facility and up to a $10,000 fine.
  • A DWI where someone is injured may be charged as intoxication assault, a third degree felony punishable by two to ten years in prison and up to a $10,000 fine.
  • A DWI where someone is killed may be charged as intoxication manslaughter, a second degree felony punishable by two to twenty years in prison and up to a $10,000 fine.

Contact experienced DWI attorney David A. Nachtigall by calling our Houston office at 713-229-0008.


“David went above and beyond to help me in defense of a DWI charge. With his background as a prosecutor, he already knew the ins and outs of navigating through the process and was able to get me a better deal than I otherwise would have received. His hard work, open communication, dedication and intelligence are all very valuable for anyone in an unfortunate situation like I was. I couldn’t be more pleased with his representation and would definitely recommend him to anyone considering hiring an attorney.”
charged with Misdemeanor
“David was the first and only person I considered calling for legal advice for a friend in an unusual and complicated situation. His advice was spot-on accurate and the best solution. David is not only one of the smartest lawyers I know but he also has a unique grasp of the nuances involved in working with different personalities and negotiating on behalf of them. He can quickly synthesize various outcomes and options into a well-defined solution. He does it all with integrity, clarity and confidence that I’d want representing myself or a loved one.”
B.S., client under Felony Investigation
“Mr. Nachtigall is an exemplary attorney. Overall, he was always responsive to the various amount of questions I had, also he kept me informed on how things were looking during my case. I have spoken to plenty of attorneys, but Mr. Nachtigall seemed to stand out for his sincerity, his willing to make your case his responsibility and maintaining a positive attitude that seem to be hard to find nowadays.”
A.R., client charged with Felony
“Within my industry I consult with many lawyers and whilst on a business trip to Houston I required legal counsel and David was recommended to me. Initially David’s age surprised me; as it did not reflect his wealth of experience, local contacts and immediate control that he took of my case and me. David promptly providing sound, logical and concise legal counsel which demonstrating a comprehensive understanding of the local system and the law. David has great integrity and a supreme confidence born from experience. A quiet man but with a firm, resolute character that enabled a professional court demeanour that when coupled with his succinct legal strategy provided for a most successful conclusion in court – Thank you David. I vouch for and strongly recommend David services, he is great lawyer.”
J.G., client charged with Misdemeanor
“David Nachtigall was my attorney for a DWI that I received in December of 2013. He really did a great job on my case. He was always very polite, prompt, and diligent when dealing with any questions that I had and he always took the correct steps to accomplish our desired outcome. Even though my case was stacked against me, he still was able to negotiate a DWI Pre-trial Intervention plea (which was the best and most realistic outcome considering the circumstances). Just to make things clear, the deal I received is not one that is easily ascertained. In fact, it took two tries to receive it. However, thanks to Mr. Nachtigall’s hard work and persistence, the deal went through. He never kept me in the dark about anything in reference to my case, he was not difficult to contact, and he always returned my phone calls as soon as possible or as soon as he had an answer to any question I asked (all of which are increasingly rare qualities in a busy lawyer). I can’t thank him enough for his help, and I would recommend David Nachtigall to anyone in need of a great, hard-working lawyer who knows how to get things done efficiently and effectively.”
J.C., client charged with Misdemeanor
“I was recently charged with assault on a peace officer which is a felon charge. I have never been in trouble with the law in my life. I was raised in a strict catholic house I was at the wrong place at the wrong time. I hired David after dealing with a bad lawyer. He picked up the slack with no problem. David did everything in his power to get the charges dropped. I left with a misdemeanor charge and 6 months probation. David answered ALL of my phone calls & emails. He showed up to every court setting and didn’t send anyone for him. I would highly recommend David to anyone.”
J.U., client charged with Felony
“David Nachtigall is a true professional. He handled my case (a second degree felony) with such expertise that the charges were dropped. His experience as a former prosecutor proved to be a tremendous asset. He kept me well informed and provided much needed personal support. I highly recommend David for any legal need you may have.”
P.S., client charged with Felony
“I highly recommend criminal defense attorney David Nachtigall. While he represented my son, David consistently displayed a calm and professional demeanor, careful attention to detail, and thoroughly researched every aspect of a very complex and challenging criminal case. His ability to deduct the truth was commendable despite the complainants who kept changing their story. I am thankful we had David on our side. His previous experience working in the DA’s office was an advantage in understanding how the courts worked. I especially appreciated his compassion to stay in touch with us and that he was easily reachable when we had questions. If you need an attorney that will truly listen and fight for you, I recommend David Nachtigall.”
P.T., parent of child charged with Felony
“David is a consummate professional. Through a normal background check I found out I had a very old warrant, I attempted to call the county and they would’t even talk to me. It could have cost me my job. I contacted David (one of the challenges is I live 500 miles away); and he secured a dismissal the next day, saving my career. He cut right through the red tape. I’d highly recommend David to anyone!”
R.B., charged with Misdemeanor
David is one of the most polished, even tempered attorneys I’ve ever met. I was the defendant on a spurious criminal case and he carefully dissected each unsubstantiated allegation and was able to refute the basis for the charge itself (which was the intent to commit a crime). I have to say that he really made the prosecuting attorney look foolish by carefully researching and laying out the facts combined with his patient, even tempered demeanor. I also appreciated the fact that he knew the behind the scenes political motivations for why the prosecution in the D.A.’s office acted so illogically-he knows these people and their work environment, so he was able to use this to craft a winning strategy to get my case dropped.
J.B., charged with Felony
“I was recently traveling on business in Houston and was caught with a tiny amount marijuana. All it takes in Texas is half a joint and you are in a world of hurt. Dumb mistake on my part. Let me be the first to advise everyone in a similar situation, you will need strong representation. The Houston court system is beyond challenging and unbelievably confusing. What I thought was no big deal could’ve meant losing my license, probation, and possibly more jail time. Typically people hate attorneys, David saved me in a huge way. He treated me like a friend and always kept me posted on the status of my case. He was willing to work with me due to my work schedule and he came to his office, before it even opened, to meet me. Because of his experience and persistence my case was dropped. I am so thankful I found him and would highly recommend his service. Trust me, you will not be disappointed.”
J.W., client charged with Misdemeanor