Dallas DWI Lawyer – Articles

What the Law Requires to Arrest for DWI

1. Police officers must have a reason for stopping your vehicle

Before a Police Officer can pull you over they must have a legitimate reason for stopping your vehicle. The most common reasons include speeding, failing to maintain a single lane, and ignoring traffic safety devices. If you obey the traffic laws and still get pulled over, there is a good chance you can get your case dismissed by a Motion to Suppress. The best way to ensure the Police do not stop your vehicle to conduct a DWI investigation is to closely follow all the traffic laws and devices in the area you are driving in.

2. If the Police stopped your vehicle for a legitimate reason, the Police must still have “reasonable suspicion” to conduct a DWI investigation.

“Reasonable Suspicion” exists if the officer has specific articulable facts which, taken together with rational inferences from such facts, reasonably justify the officer to believe that a particular person has engaged or is engaging in a criminal activity. Terry v. Ohio, 392 U.S. 1, 21 (1968). In simple terms the Police are looking for certain signs that would indicate you are driving while intoxicated. Police officers are taught to look for the following symptoms of impairment. If only a few of these signs are present an officer will have “reasonable suspicion” to conduct a DWI investigation. This list is based on research conducted by the National Highway Traffic and Safety Administration (NHTSA).

  • Flushed face
  • Red, watery, glassy or bloodshot eyes
  • Odor of alcohol on breath
  • Slurred Speech
  • Fumbling with wallet while trying to get license
  • Failure to comprehend officer’s questions
  • Unsteady of feet while exiting vehicle
  • Swaying while standing
  • Leaning on car for support
  • Being combative, argumentative or jovial while talking with officer
  • Disheveled clothing
  • Lack of awareness in regards to time and place
  • Unable to follow police instructions

3. After the Police have conducted their investigation, they only need “probable cause” to arrest you for DWI.

The definition of probable cause is “a reasonable belief that a person has committed a crime.” The issue is this definition is not a bright line rule or test. It is a belief based on the officer’s training and experience. Probable Cause is a higher burden of proof than the reasonable suspicion the police need to conduct their DWI investigation, but it does not determine guilt or innocence. In a DWI investigation a police officer bases his belief of probable cause on the evidence you provide by your looks and actions at the scene, the standardized field sobriety tests, and/or the breath or blood tests. The less evidence the police have, the harder it is to prove you were driving while intoxicated. If you refuse to do every test the police offer, you will in essence have given the police no evidence by which to establish probable cause. However, the police will use this refusal to substantiate their beliefs and this will allow them meet their burden of probable cause. It is important to remember that just because the police have probable cause to arrest you, this does not equal guilt.

If you need a DWI attorney in Dallas, you should contact experienced Dallas DWI lawyer Mark T. Lassiter.

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You know when you seek medical care; you put your life in the hands of doctors. You want someone to fight for you as they would fight for themselves. The same occurs with an attorney and Mark is definitely someone that will fight for you.

Dr. Patrick W.

I was arrested in March 2010 for suspicion of DWI, and had blown a 0.18. I retained Mark 3 days later and through his hard work and diligence my case was dismissed without my ever having to appear in front of a judge. His knowledge of criminal law is incredible, and he is very kind, and was incredibly respectful and encouraging throughout this entire harrowing process. Previous to this arrest I had never had so much as a speeding ticket and I came into this extremely scared and terrified of the long term implications of a DWI conviction in Texas, as Texas is not a state that allows adjudication and I am an RN who made one incredibly bad decision, but a conviction on DWI could cost me my license to practice. I chose Mark on the recommendation of several people whom I trust, and I am so glad I did! His staff is very courteous and helpful, and his track record is impeccable! I honestly didn’t dare hope that I might be so fortunate as to get my case dismissed, but Mark came through for me with flying colors! Thanks to Marks knowledge and hard work I will be eligible to have this arrest expunged from my record in two years, and can relax knowing that my license to practice is safe. Mark was also always willing to hear me out and never tried to pressure me into anything I was uncomfortable doing, he returned my calls and emails within hours and did everything he could to reassure me that while there was a great deal of gravity to the situation I had landed myself in, that he would champion my cause. I made a terrible, terrible choice, and I am so grateful and fortunate the no one was hurt. I owe so much to Mark, and I will never be able to thank him enough for his hard work on my behalf.


Obviously you have accessed Mark Lassiter’s website, please bear with me while I inform you about your good fortune. Unfortunately I found myself retained by the Garland Police some time ago on a DWI charge. I have never heard any of my friends/co-harts discuss this subject. Due to the personal humiliation of the circumstances, this is not something that I would approach them on either. So I had to rely on Google to find attorneys that dealt with this type of thing for Garland. Finding multiple hits I began the review of websites until I accessed M. Lassiter’s. I was extremely impressed. I made contact with him with the normal trepidation of retaining an unknown individual for such a sensitive personal matter. Little did I know at the time of my good luck. During the course of my case, a couple of attributes I learned about M. Lassiter are as follows: · He was very capable, and never lost focus of my case and best interests · He was easy to talk to and actually listened and responded to the pros and cons of my standpoints · He is a very personable and energetic person Ultimately I am sure you will find retention of M. Lassiter a most beneficial partnership in the resolution of your case.

Best Regards, Rita L.

In need of legal representation, we researched qualified attorneys in the Dallas Area. At our initial consultation with Mark Lassiter, he discussed his fees, plan of action, and potential outcomes of the case.  We found him to be not just competent, but detail-oriented and thorough.  His knowledge of the law and court proceedings was comforting. Mark Lassiter kept us informed of progress, and was able to resolve the case as quickly as possible.  Through his diligence, we got the best possible outcome. We would highly recommend his services to anyone who asks.

Bob and Jill

I found information regarding Mark by searching the web while in Illinois and my son was needing representation in Tarrant County Texas. Mark returned every single call I made, and every email I sent. I believe that Mark is a fair and honest and will try to do what is best for who he represents.


I had never been in trouble with the law. I had no idea who to call or what to do and I was certain this was going to hang over me the rest of my life. Mark took care of everything. From the first conversation he put my mind at ease and assured me everything was going to be OK…and he was right. He literally made it GO AWAY! Thank goodness. Now, that one moment of my life will not ever define who or what I am.


I’ve finally found a lawyer I can count on.

Cody B.

I switched from my original lawyer to you because you made sure I understood the entire process.

Amanda H.

My family and I will always be indebted to you.

Lisa L.

You were able to help me win my case when I didn’t think anybody could.

Roger C.

I would never use or recommend anyone else for anybody else for a criminal manner.

Cory M.

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