The Intoxilyzer 9000 in Texas DWI Cases: What You Need to Know

If you have been arrested for Driving While Intoxicated (DWI) in Texas, chances are the results of a breath test will play a major role in your case. In most jurisdictions across the state, law enforcement uses a device called the Intoxilyzer 9000 to measure blood alcohol concentration (BAC). Prosecutors rely heavily on the results produced by this machine, often treating them as definitive proof of intoxication. However, the reality is far more complex.

At Griffin, Cain & Herbig, Attorneys at Law, PLLC, we represent clients facing DWI charges across Conroe, The Woodlands, and Montgomery County. We understand how the Intoxilyzer 9000 works, and more importantly, how its results can be challenged in court. This page explains the basics of the device, how it is used in Texas, and what your legal options may be if you are facing a DWI based on its results.

What Is the Intoxilyzer 9000?

The Intoxilyzer 9000 is a breath-testing device manufactured by CMI, Inc. It is designed to measure a person’s BAC by analyzing a sample of deep lung air. When you blow into the device, it uses infrared spectroscopy to detect the presence of ethanol, the type of alcohol found in alcoholic beverages. The machine calculates an estimated BAC and records the results for use in court.

Texas began adopting the Intoxilyzer 9000 as a replacement for older models such as the Intoxilyzer 5000. The newer model is considered more advanced and more accurate, although it still has limitations. The Texas Department of Public Safety (DPS) oversees the operation, certification, and maintenance of these machines statewide.

How the Intoxilyzer 9000 Is Used in DWI Cases

When a person is arrested on suspicion of DWI, the arresting officer may request that the individual submit to a breath test at the police station or jail. This is different from the portable breath test device used on the roadside, which is generally not admissible in court.

The Intoxilyzer 9000 is considered an evidentiary device. That means its results can be presented in court as part of the prosecution’s case. The machine records the BAC result, the time of the test, and other information such as the operator’s certification number and the device’s calibration status.

Legal BAC Limits in Texas

Texas law prohibits operating a motor vehicle with a BAC of 0.08 percent or higher. For commercial drivers, the limit is 0.04 percent. For drivers under the age of 21, Texas follows a zero tolerance policy, meaning any detectable amount of alcohol can lead to charges.

A result above the legal limit is often enough for the state to proceed with prosecution. However, the breath test result alone is not always accurate or reliable. It is just one piece of the puzzle.

Factors That Can Affect the Accuracy of the Intoxilyzer 9000

While the Intoxilyzer 9000 is a sophisticated device, it is not perfect. Several factors can cause false readings or affect the accuracy of the results. These include:

Operator Error

Only certified operators are allowed to administer breath tests using the Intoxilyzer 9000. If the person administering the test was not certified, failed to follow proper procedures, or did not observe the required waiting period before testing, the results may be challenged.

Improper Calibration or Maintenance

The machine must be regularly calibrated and maintained according to DPS guidelines. If maintenance logs show gaps, missed service dates, or failed tests, the reliability of the result may be questioned.

Medical Conditions

Certain medical conditions, such as GERD (gastroesophageal reflux disease), diabetes, or recent dental work, can cause the machine to detect alcohol from the mouth or stomach that is not truly reflective of blood alcohol concentration.

Mouth Alcohol

If a person recently consumed alcohol, used mouthwash, or vomited before the test, residual mouth alcohol may inflate the BAC reading. The operator is required to observe the subject for at least 15 minutes before administering the test to avoid this problem.

Rising BAC

Alcohol does not affect the body immediately. Your BAC may continue to rise for 30 to 90 minutes after your last drink. That means your BAC at the time of driving may have been lower than your BAC at the time of testing. The Intoxilyzer 9000 cannot account for this time delay.

Challenging Breath Test Results in Court

A failed breath test is not an automatic conviction. A skilled DWI defense attorney can challenge the validity of the Intoxilyzer 9000 results using several strategies. These include:

• Requesting the maintenance and calibration records for the machine
• Subpoenaing the operator’s certification and training records
• Reviewing video footage of the test to determine if the correct procedure was followed
• Consulting with experts in forensic toxicology or breath testing technology
• Filing motions to suppress the test results if your rights were violated

In some cases, we are able to show that the breath test result is unreliable or inadmissible. In others, we use these flaws to negotiate for reduced charges or to dismiss the case entirely.

Your Rights During a Breath Test

Under Texas law, you have the right to refuse to submit to a breath test. However, refusing may trigger an automatic license suspension under the Administrative License Revocation (ALR) process. You must request a hearing within 15 days of your arrest to contest this suspension.

It is important to understand that while you can refuse a breath test, the officer may obtain a warrant to take a blood sample. Also, your refusal can be used as evidence in court to suggest that you were trying to hide intoxication.

Whether you submitted to the Intoxilyzer 9000 or refused, you still have legal options. Our team will help you understand your rights and determine the best course of action.

Contact a Texas DWI Defense Lawyer Today

Breath test results are often presented as conclusive, but they are not above challenge. If you are facing DWI charges in Texas and the Intoxilyzer 9000 was used in your case, you need a defense team that understands the science and the law.

At GCH Lawyers, we have the experience and resources to challenge faulty evidence, protect your rights, and pursue the best possible result. We represent clients in Conroe, The Woodlands, Montgomery County, and surrounding areas.

Call 936-539-1011 or fill out our online form to schedule a free, confidential consultation.