DWI Urine Test

Officer utilize various types of chemical testing when calculating blood alcohol concentration (BAC). One type of tests commonly used to determine a person’s BAC is urine analysis. For this type of test, officers will ask the driver to submit a urine sample. The sample is then tested as a state lab or at the local hospital and technicians will then determine if the person was inebriated while driving on alcoholic beverages or a controlled substance(s).

Officers tend to use urine testing when they suspect you’re under the influence of drugs. That is because lab technicians detect the different terpenes in your system using urine analysis. These terpenes can then indicate that you’ve used drugs previously and which type of drug you were using. The issue with urine testing is that often it will pick up on old terpenes still in your system. This means lab reports will state you have drugs in your system even if you hadn’t consumed any substance in days, weeks, or even months. Other factors including human errors could contribute to faulty or skewed urine test results.

For these reasons and more, it’s imperative you seek legal representation if you’ve been arrested for DWI due to a failed urine test.

DWI Urine Test Houston Lawyer | Harris County Drunk Driving Attorney

If you or someone you know has been charged with driving while intoxicated via a failed urine test, it’s within your best interest to call The Benken Law Firm. Brian Benken has an in-depth understanding behind the science of DWI chemical testing including urine analysis. He has challenged hundreds of faulty urine test results since 1991 and can utilize his past experiences to help you.

Call The Benken Law Firm today at (713) 223 - 4051 to set up your first consultation with Brian Benken. He has offices in Houston and accept clients throughout all parts of Harris County and Texas including Bellaire, West University Place, and Bunker Hill.

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Urine Alcohol Test Results Explained

In Texas, law enforcement uses various types of chemical testing to calculate blood alcohol concentration (BAC) including blood tests, breathalyzers, and urine analysis. Officers tend to refer to breathalyzers when they pull over a person for driving under the influence. However, if the officer suspects the person is under the influence of drugs, they may ask them to instead undergo a urine test.

Law enforcement utilize urine analysis when they suspect a driver is impaired by a controlled substance or substances. They do this because urine analysis is much more accurate at identifying drugs and their terpenes. The test specifically measures the number of grams of alcohol per 67 milliliters of urine.

What’s concerning about urine testing is that it can detect what is in your system accurately, but it can’t test for when you consumed said substance. Since different drugs terpenes can remain in a person’s system for longer than others, that means you could test positive for drugs even if you hadn’t used any in days, weeks, or even months.

For example, Diazepam stays in your system for a minimum of 10 days. If you used the drug in the last week and underwent urine analysis, the test results may indicate you used Diazepam. Officers may then take this information and use it as evidence of your impairment while driving.


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Can I Refuse DWI Urine Testing?

Despite common misconceptions, you are legally permitted to refuse any type of DWI chemical test including urine analysis. However, if you refuse testing it’s important you understand you may face an administrative penalty. That is because refusing DWI chemical testing is technically a violation of implied consent laws in the state of Texas.

Implied consent laws under the Texas Transportation Code state a person who drives on Texas road’s is implicitly agreeing to comply with DWI chemical testing by law enforcement. Any refusal would constitute as a violation and therefore result in an automatic administrative license suspension by the Department of Public Safety.

If you refuse urine testing, DPS will automatically suspend your license for the following terms:

  • 180 days for a first-time refusal
  • 2 years for a second or subsequent refusal

It can be incredibly difficult to navigate the state of Texas without a vehicle, but most attorneys would recommend you refuse urine testing from law enforcement anyway. If you refuse to submit, then the prosecution will have no evidence of your impairment other than subjective testimony from the officer and possible eyewitnesses. It will ultimately stunt their case and therefore your defense will have an easier time fighting for reduced or dismissed charges.

Also, you still have a chance to contest your administrative license suspension and maintain your driving privileges. You can file a request for an Administrative License Revocation hearing (ALR) to challenge your suspension, but you will only have 15 days after your arrest to do so.

It’s important to understand if you “fail” a urine test you will still face an administrative license suspension by DP. If you comply with urine resting and fail, then you license could be suspended up to:

  • 90 days for the first offense
  • 1 year for a second or subsequent offense

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How Accurate are Alcohol Urine Tests?

Urine analysis, although based in science, is known to not always be the most dependable method to calculate BAC or terpenes. Test results may be skewed by outside factors including contaminated samples, diluted samples, and using faulty test kits. In addition to this, the test itself detects terpenes that may have been in your system for days, weeks, or even months. Officers may inaccurately believe you were high on drugs while driving because the test results indicate you have terpenes in your system.

Listed below are some detection times for common controlled substances that may be identified based on their terpenes during urine testing.

Drug: Detection Time:
Marijuana Daily Use 10 days
Marijuana Chronic Use 30 days
Cocaine One day
MDMA, Ecstasy, or Molly Two days
Codeine Three Days
Ketamine Two days
Hydrocodone Three Days
Amphetamine Three Days
Methamphetamine Three Days
Fentanyl Three Days
Flunitrazepam Five Days
Morphine Three Days
Methadone Seven Days
Diazepam 10 days
Phencyclidine (PCP) Eight days
Oxycodone Three Days

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Additional Resources

Texas DWI Laws – Visit the official website of Texas Penal Code to learn more about driving while intoxicated (DWI) and other related offenses. Access the site to learn more about DWI charge specifics, penalties, aggravating factors, and other important information.

Administrative License Revocation Program – Visit the official website of the Texas Department of Public Safety (DPS) to learn more about administrative penalties for refusing chemical testing. Learn the suspension terms for minors, non-commercial adult drivers, and commercial drivers (CDL holders). You can also find a link to file a request for an administrative license revocation hearing.


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Harris County DWI Lawyer | DWI Urine Testing, Harris County Texas

If you or someone you know has been arrested for driving while intoxicated, then it’s crucial you contact a skilled criminal defense lawyer with The Benken Law Firm. Brian Benken has been practicing criminal defense for decades with a special focus in DWI. His in-depth understanding behind the science of urine testing, blood testing, and breathalyzer tests may be the advantage you need to beat your DUI charge.

Call The Benken Law Firm today at (713) 223 - 4051.


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