Texas Implied Consent Law

Robert Frank Borkenstein developed the breathalyzer in the 1950s as a mechanical device to record and estimate the blood alcohol content (or BAC) of an individual. When it was first invented, breathalyzers also tested for disease and viruses, but now it is used solely as a DWI (driving while intoxicated) testing device for law enforcement. Though helpful to some degree, the breathalyzer test is not always accurate, which isn’t the most encouraging news since testing is now mandatory under Texas implied consent law.

What is Implied Consent?

Implied consent refers to “the agreement given by a person’s action (even just a gesture) or inaction, or can be inferred from certain circumstances by any reasonable person. The person who gives consent can withdraw the consent anytime and should have the capacity to make valid consent,” according to Cornell Law.1

What is Texas Implied Consent Law?

Texas’ implied consent law extends to anyone with a state driver’s license. Known as an implied consent state, Texas Penal Code states that motorists who have been granted a license by the state have consented to submit to chemical blood alcohol testing, via blood or breathalyzer, whenever they are asked by a law enforcement official. Chemical blood alcohol testing is another type of test that can determine the amount of alcohol that has been consumed by a driver.

A Driver’s License in the State of Texas Implies Consent

In any state that has an implied consent law, such as Texas, when you apply for a license or drive a vehicle with that license, you are considered to have given consent to take a blood alcohol content test such as a blood test or breathalyzer. The type of test administered may vary, but all chemical testing is covered under the implied consent law. 

What Happens if You Refuse a Breathalyzer?

If a person doesn’t submit to testing, they can have their license suspended and receive penalties. A warrant may be filed upon refusal, and the refusal may be presented as evidence in any upcoming criminal trial the driver faces.  In Texas, checkpoints may be deemed “no refusal,” meaning these enforce the state’s implied consent law, typically manned by judges that are able to sign a warrant and nurses that can draw blood for the testing. With “no refusal” checkpoints, there can be an expedited process for obtaining the testing that the driver refused.

Can Refusing a Breathalyzer Jeopardize Your Driver’s License?

Under Texas’ implied consent law and per the Texas Department of Public Safety, if you refuse a breathalyzer or any other blood alcohol content test, your license will be immediately suspended. A civil process will begin called the Administrative License Revocation, or ALR, immediately after your arrest. The officer will take your license and give you notice of its suspension right after refusing to submit to testing. A 15 day period will be set after your arrest in which you may request a formal hearing about the ALR, and you will receive a temporary permit for those 15 days. If no hearing is requested, it is assumed that you have waived your right to contest the charges, and a default judgment will be entered. If you have a hearing, the judge will not be the same as the judge that presided over your DWI case.

What Can You Do to Defend Yourself if You’ve Submitted to a BAC Test?

If you’ve submitted to a blood alcohol content test, a few things can be done to help you. Before we get into specifics, let’s review legal BAC standards. In Texas, alcohol intoxication is a BAC of 0.08 or higher on a breath or blood sample. Texas Penal Code 49.01(1) shows the concentration as grams of alcohol per 67 ml of urine, 100 ml of blood, or 210 ml of breath. Blood tests are harder to fight, so submitting to a breathalyzer may work to your advantage. Blood will measure that volume directly, while urine and breath are indirect methods. While what type of test you receive is at the discretion of the arresting officer, any test resulting in a BAC of 0.08 or higher will fulfill the requirements for a DWI arrest.

One way to contest testing at trial is to expose issues with the BAC testing machine itself. Some breathalyzers do not measure for ethyl alcohol specifically and, therefore, can pick up a reading from breathing in blue, paint, car aromas, or chemical cleaners. By invalidating the measurement, you can work toward contesting your DWI.

You can also contest the BAC test results. Any device has a margin of error, some as much as 0.01%, so if your test is close to being under the limit, this can be a viable defense option. There can be an argument for blood sample fermentation if the blood wasn’t stored well. Another defense tactic can be the rising blood alcohol defense, where the driver pleads that he wasn’t under the influence while driving, but during the course of the traffic stop and field sobriety testing it rose to be over the limit. This brings into play a person’s metabolism and other biological factors.

There are several ways to defend against a submitted BAC test, and which one is in your best interest can be determined by a trained DWI lawyer. 

Know Your Texas Implied Consent Law Options

Whether you have refused testing and been forced to submit via Texas’ implied consent law or willingly took a BAC test at a stop, getting an expert defense attorney can help you. Expert counsel can help explain the laws, help you at the arraignment, advocate for a bond, preserve evidence that may be beneficial in your case, and get any incriminating evidence disclosed. Attorneys can also get your ALR hearing set up quickly, well within the allotted 15 days, to help you keep your driver’s license. They can also represent you at the ALR hearing.

Expert lawyers that specialize in DWI cases can help minimize the damage of a DWI charge and should be consulted as soon as possible to ensure that evidence isn’t lost, and your case isn’t mismanaged.


1. https://www.law.cornell.edu/wex/implied_consent

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