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DWI Blood Testing

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The legal standard for intoxication in Texas is a .08 blood alcohol level (BAC), which can be measured by breath or blood. To find it in blood, it is measured against 100 milliliters of your blood. A blood test is the last thing you want to happen. It’s invasive and unpleasant, plus it’s harder to fight in court. Both blood and breath tests have their fair share of flaws, but contesting a blood test requires a little more footwork.

If you have failed a blood test in Texas, contact attorney Mark Thiessen at 713-864-9000. Mark is available 24 hours a day, 7 days a week to ease your concerns and protect your freedom.

He has won 4 blood test trials, with a strong victory for .19 blood alcohol level. He lost one trial in 2013 and had a hung jury on two other blood test trials.

Do I Have to Give the Police a Blood Sample?

It is your constitutional right to refuse a blood test. HOWEVER, if you can you should avoid getting to this point because Texas can suspend your license and use your refusal as evidence in future prosecutions against you.

Blood Alcohol Testing Procedures

Before having to refuse or consent to a blood test, you will normally have the option to take a breath test and/or a standard field sobriety test first. If you refuse to take all of these, they will take you to the police station and read you your rights regarding the blood-alcohol tests. Then here’s what you do:

  1. Ask them what happens if you refuse the breath test again.
  2. Most officers will answer that if you refuse the breath, they will take your blood instead.
  3. After they’ve said this, take the breath test over the blood test!

In most scenarios, officers cannot take your blood until you refuse a breath test. If you fail either test, you may lose your driving privileges: 90 days for a first offense and one year with suspicion or conviction of alcohol-related charges within the preceding 10 years.

When You HAVE to Give Them Blood

Texas has recently implemented no refusal weekends, which aren’t just limited to holiday weekends. During no-refusal time periods, the Texas Supreme Court allows police officers to draw blood without your consent, based only on probable cause.

If you resist, they really will strap you down to a chair using as many officers as they deem necessary until they have gotten your blood. If this happens, don’t fight. At that moment, there is no way around it and you don’t want to risk suffering bodily harm from the police – or an assault charge if they feel you fought back too hard. Afterward, you should contact a qualified DWI or DUI lawyer as soon as possible to rectify the situation.

Few Lawyers Can Help if You Fail a Blood Test

The truth of the matter is that less than 1% of lawyers are skilled enough to win a DWI case if you’ve failed a blood test. It’s one reason lawyers recommend that you avoid blood tests entirely.

As a trial attorney focusing on complicated DWI cases, Mark Thiessen is one of the few attorneys trial-tested and proven in this area of the law. Not only does he know constitutional and DWI law inside and out, but he understands the scientific and technical aspects of these cases better than the experts. Mark Thiessen has won three blood test trials where the blood comes into evidence and the jury returns a verdict of Not Guilty (.022, 0.19 and 0.09). Anyone can win a trial with the blood suppressed. You need an attorney who can win with the blood coming in.

At best, blood tests are an approximation of your BAC with an “acceptable” error range of error, but even so, a comprehensive understanding of the number of scientific fields is required to effectively argue a blood test case in court. Any given DWI or DUI case may require courtroom back-and-forth involving anatomy, physiology, toxicology, chemistry, medicine, chemical testing, computer science, biology and even physics.

NOTE: This information is not legal advice. It is provided for educational use only. If you’ve been forced to take a blood test in Texas, contact the lawyer who can help. Call Mark Thiessen at 713-864-9000, or fill out a briefcase evaluation form.

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