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DWI Blood Test

In some cases, a breathalyzer test isn’t enough for officers to determine a person’s impairment level. Law enforcement may ask you to submit to a blood draw for a more accurate reading, especially if they suspect you’re under the influence of an illegal controlled substance. These blood tests, although more accurate than other forms of chemical testing, can lead to skewed results and false BAC readings due to underlying factors.

To accurately read a DWI blood test, it must be translated by someone with a scientific background. Normally this person is a lab technician of sorts and not the officer themselves. Since the information is passed from person to person it can lead to issues with chain of custody. In the end, this can greatly affect a person’s blood test results and possibly lead to a false positive BAC reading. Some factors that can skew a blood test can include contaminated samples, improper storage or using outdated testing kits.

If you or someone you know has been charged with DWI due to a blood draw, it’s important you seek legal representation for you.

DWI Defense Lawyer for Blood Tests in Conroe, TX

DWI accusations and charges can make a serious impact on your life. You could have your license suspended, pay large fines, be required to take a DWI class and even face a possible jail or prison sentence. Because of these consequences, we highly suggest you hire an experienced criminal defense attorney if you’ve been arrested for driving under the influence.

To find a quality defense by lawyers who have a special focus in DWI, call Evans & Powell, PLLC. Collectively our defense attorneys have decades of experience defending others accused of DWI. We want to guide you through this legal process so you can get the best possible result for your case. Call us now at (713) 622 - 2000 to set up your first consultation free today.

Evans & Powell, PLLC accepts people throughout the greater Montgomery County area including Willis, Montgomery, Conroe, New Caney, Splendora and Magnolia.

Overview of DWI Blood Tests in Texas


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Why Use Blood Analysis for DWI Testing?

Police officers use a variety of chemical tests to calculate a person’s blood-alcohol concentration (BAC) level such as breath analysis or urine analysis. These chemical DWI tests are normally used against people who are suspected of drinking and driving. However, when officers suspect someone is under the influence of drugs and driving, they may instead ask the state or private crime lab to run a blood sample analysis.

Blood draws are a much more accurate way to determine a person’s impairment level when they’re on drugs. Since blood analysis gives the most accurate results out of the three tests, officers tend to use it for those who are driving while under the influence of a controlled substance. An officer may also have a person undergo a blood test if they are involved in an deadly accident and they are unconscious as a result.


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Issues with DWI Blood Analysis

Any test, whether chemical or physical, is susceptible to human error. Both external and environmental factors can lead to false positives and jeopardize your freedom because of it. Some of these factors can include contaminated samples and outdated testing equipment.

Listed below are some issues associated with DWI blood testing.

  • Poorly stored sample;
  • Alcohol contamination of the sample during sterilization;
  • Break in chain of custody creating confusion;
  • Inability to convert serum or plasma blood;
  • Second blood test gives vastly different results;
  • The sample was taken by an unauthorized person;
  • Outdated testing kit;
  • Failure to sterilize medical equipment;
  • Sample decomposition;
  • Mislabeled sample;
  • Inadequate training;
  • Break in chain of custody creating confusion;
  • Contaminated samples;
  • Unsanitary testing conditions; and
  • Failing to take two samples

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Should I Refuse Blood Testing for DWI in Texas?

Many attorneys are asked the question; “should I refuse or submit to DWI testing?” When it comes to blood analysis the answer is up to you, but many attorneys would recommend you refuse. An abundance of factors could influence the results of your test and lead to a misleading BAC reading, which will cause you to have DWI charges.

However, before you refuse testing it’s imperative you understand the administrative consequences that go alongside it. If you refuse chemical testing your license could be suspended for up to 180 days. A repeat refusal can mean an enhanced suspension term that can last up to two years.

While it’s true a suspended license is frustrating, it’s much easier to handle than a criminal DWI conviction. When you refuse DWI testing it means the prosecution will have little to no evidence against you. It will be much harder for the district attorney to convict you without having concrete scientific evidence against you. Submitting and failing a DWI blood test will give the prosecutors ample fire for your case and will likely increase the chances of conviction.

As a final note, it’s important you understand that if you refuse chemical testing you could be arrested as a result. Officers have the right to make a lawful arrest if they have probable cause you’re under the influence and driving. For some police officers, a refusal is an indication of guilt and enough probable cause to arrest.

While an arrest is scary, you must remember that it doesn’t mean you will be charged necessarily. Additionally, the arrest and booking process is only temporary. You may be booked for a short period of time, but in the end the prosecution will have little evidence to use against you. In the end, you may be granted bail and only must face a suspended license instead of serious driving while intoxicated charges.


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Additional Resources

Administrative License Revocation Program – Visit the official website of the Texas Department of Public Safety (TxDPS) to learn more about their ALR program and how it could help you with your suspended license. Access the site to read about their suspension terms, ALR hearing and how to get an occupational license and other related issues.

Texas DWI Laws – Visit the official website of the Texas Penal Code to learn more about their driving while intoxicated laws. Access the site to read their penalties, possible defenses, implied consent laws and other alcohol-related offenses in Texas.


Blood Analysis Lawyer in Montgomery County, Texas

If you or someone you know has been charged with driving while intoxicated, it’s important you find a practiced and skilled attorney. We suggest you find a defense lawyer with a special concentration in DWI like the legal team at Evans & Powell, PLLC. Our lawyers have the experience needed to fight for your rights and the passion to go up against any charge, no matter how severe.

Call us now at (713) 622 - 2000 to set up your first consultation absolutely free. Evans & Powell, PLLC will create a defense plan that will fit your needs to battle for your rights. We will do whatever possible to battle your charges. You can find us in Conroe, but we represent people throughout the greater Montgomery County area including Willis, New Caney, Splendora, and Montgomery.

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