Portable Breath Test Devices at DWI Arrest

Posted by Doug Murphy | Dec 25, 2021 | 0 Comments

A recent media report of a Porter, TX DWI arrest provides an extreme example of a case involving the use of a portable breath test device at the scene of the DWI arrest. The point here is to consider the reliability of portable breath test devices. Two circumstances, though, make that question of reliability or unreliability even more important for the defendant driver in this particular case. The media report indicates that the driver nearly struck the officer's squad car as the officer monitored traffic near the arrest scene before swerving into oncoming traffic. The media report further indicates that this incident was the defendant's eighth DWI arrest. The Conroe woman faces a charge of DWI third or more, which is a third-degree felony bringing a sentence of two-to-ten years and a fine up to $10,000.

Portable Breath Test Devices

An eighth DWI is much more likely to bring a maximum rather than a minimum penalty. That likelihood of a much stiffer sentence makes the above defendant's aggressive DWI defense all the more critical. An aggressive DWI defense often entails challenging the reliability of the blood or breath test. Portable breath test devices are in use among Texas police forces and the forces in other states. Indeed, anyone can buy a portable breath test device for as little as $26.99 on Amazon. So-called professional-grade devices cost about $100 more than that. Many Texas police departments use an Intoxilyzer 9000 model that costs far more, thousands of dollars.

Texas Law on Breath Test Devices

For the prosecution to base a DWI charge on a portable breath test device, Texas law requires that the police officer administering the test must do a lot of things right. Portable breath test devices are so unreliable that Texas law imposes stringent requirements on their use for DWI prosecutions. Among other DWI toxicology requirements, the police must:

  • follow specific guidelines for testing, administered and overseen by the Texas Department of Public Safety's Breath Alcohol Laboratory
  • obtain Department of Public Safety certification for breath testing
  • individually certify all breathalyzer operators to perform the test, after training them to specific standards for using the specific breath test device
  • calibrate and certify all breath testing machines to Standardized Field Sobriety Test standards that the National Highway Traffic Safety Administration establishes
  • document the maintenance and calibration of the breath test device and produce the documentation on request
  • provide the defendant with the official warning form that law requires before conducting the testing
  • obtain the defendant's signature on the official form after the officer explains the testing procedure
  • conduct the test a second time after the first test produces its report to show any variance between results

Texas DWI Defense Attorney Challenges Breath Testing

DWI toxicology is not for the faint of heart. Only highly skilled and experienced DWI attorneys really know how testing devices are supposed to work and how police misuse them, producing unreliable results. If you or someone you love faces a DWI charge based on breath testing, Texas DWI Specialist attorney Doug Murphy has experience is demonstrating in beating breath and blood testing in trial and is available for expert representation. Attorney Murphy's fellow lawyers voted him Best Lawyers in America 2021 Lawyer of the Year. He is also one of only two Texas lawyers holding both Criminal Law Certification and DWI Board Certification. Contact Doug Murphy Law Firm online or at (713) 229-8333 for your DWI defense today.

About the Author

Doug Murphy

Doug Murphy is one of only two Texas lawyers Board Certified in Criminal Law by the Texas Board of Legal Specialization, and also in DWI Defense by the National College for DUI Defense, accredited by the American Bar Association and the Texas Board of Legal Specialization.


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