Getting pulled over under suspicion of DWI is scary as hell. There’s a lot going on, and most people have no idea what to do. What do you say to the cops? Do you have to do those sobriety tests? Can you refuse a breathalyzer?
If you get pulled over in Texas and the police have reason to believe you’re intoxicated, they will probably ask you to take a breath test. Whether you should or should not take the breath test is a longer discussion, which we’ll expand on here, but we can tell you now: you don’t have to take the breathalyzer test, but there are consequences for refusing one.
Keep reading to find out how and why you might refuse a breathalyzer, what we recommend you do if faced with the question, and what some of the consequences for refusal might be — or, if you or a loved one has already been charged with DWI in Houston, call Thiessen Law Firm today at (713) 864-9000 for winning defense.
Can you refuse a breathalyzer in Texas?
Up top, we will reiterate that yes, you can refuse a breathalyzer test in Texas, but doing so comes with pretty much automatic legal consequences.
While you are legally allowed to refuse a breathalyzer test, thanks to your duty of care to other drivers and Texas’ implied consent laws, you agree to submit to certain testing by being on the roads at all in Texas.
To be honest, if you refuse to take the breath test, it often means that a warrant for your blood is just around the corner. Why is that? Because of those implied consent laws.
Implied consent laws and breathalyzers in Texas
When you apply for and obtain a driver’s license in Texas, you also enter into what is called an implied consent agreement. This means that you agree to follow the rules of the road, including those related to drinking and driving. This also means that you are subject to requests from police officers to submit to a breath or blood test.

However, because it is deemed unconstitutional to force an individual to take a breath or blood test without a warrant, you are legally allowed to refuse a breathalyzer test unless there was a serious injury or death involved or you have a previous DWI conviction on your record. So if you’re pulled over in Texas and a police officer asks you to take a breathalyzer test, you can refuse, but you’re breaking implied consent laws.
Refusing the breath test can result in automatic license suspension of 180 days – 2 years and, while it is not an admission of guilt, it doesn’t help your DWI lawyer with your case — especially if the police blood test you right after.
That’s right: if you refuse to take a blood test (aka a blood alcohol content (BAC) test), a police officer can request a warrant to take your blood. If the warrant is granted, then they are legally allowed to take your blood. At this point, further refusal will result in further consequences.
Continue reading: What is a chemical test?
Is it a good idea to refuse a breathalyzer?
Whether or not refusing a breathalyzer in Texas is a good idea really depends on your individual situation. Why are you refusing? Do you have access to a good lawyer? Have you been drinking, and if so, how much? What’s your criminal history like? Despite what many people think, we believe that “Do Not Blow” is bad advice. Why?
If you’re going to submit to a test, a breathalyzer is almost always a better idea than a blood test. Blood tests are incredibly accurate (and can also measure for drugs in your system), while breath tests are much more susceptible to error.
Keep in mind that there are exceptions to this rule — one of which is if you think you may have a particularly high BAC; consequences for DWI with 0.15 alcohol level and above are more severe, and taking the ride down to the station will give your body time to work off some of that alcohol, usually at around .02 BAC an hour.
What happens if you refuse to do a breath test?
As we mentioned earlier, there are automatic consequences when you refuse to take a breathalyzer test. Namely, refusing a breathalyzer almost always results in a 180-day license suspension at minimum.
Now, you might be thinking, “A 180-day license suspension is definitely not as bad as a DWI conviction.” And if you think about it that way, then you would be correct. But refusing a breath test doesn’t mean you’re off scott-free for DWI: even if you refuse to submit to a test, you can still be arrested for DWI if the police officer has probable cause.
Probable cause for DWI arrest comes in many forms, including but not limited to a breathalyzer test. For example, Texas field sobriety tests are very easy to fail, and if you’ve committed a traffic violation or even looked or smelled as if you’ve been drinking, that’s enough probable cause for an arrest.
To summarize, what often happens after refusing a breathalyzer is:
- Your license will be suspended automatically.
- The police will attempt to get a warrant for blood draw, allowing them to perform a more accurate test.
- The prosecution will attempt to use your refusal as an admission of your guilt.
- You will likely face harsher penalties if you do face a conviction.
Continue reading about sobriety tests:
The science of measuring blood alcohol content
Blood alcohol content (BAC) is measured using breath or blood tests, but the science behind these methods is more complex than most people realize.
- Breathalyzers estimate BAC by analyzing alcohol molecules in a person’s breath, using infrared spectroscopy or fuel cell technology to convert the breath alcohol concentration into a BAC reading.
- Blood tests use gas chromatography to separate and quantify alcohol in a blood sample — a much more accurate process.
The important thing for you to know is that both these methods are highly flawed; improper calibration, contamination, or procedural errors lead to inaccurate results all the time. That’s why having a lawyer who knows the science by your side, like ACS-CHAL Forensic Lawyer-Scientist Mark Thiessen, is crucial when going to court for a DWI.
Refusing a breathalyzer — FAQs
Are you guilty if you refuse a breathalyzer?
No, refusing a breathalyzer does not automatically make you guilty of DWI, but it can be used as circumstantial evidence that can impact a judge or jury’s decision. Prosecutors will likely try to argue that your refusal indicates you were attempting to hide that you were over the legal drinking limit.
Can breathalyzers be wrong?
Can a breathalyzer be wrong? YES. Breathalyzers produce inaccurate results all the time due to a number of factors which can include:
- Improper calibration
- Medical conditions
- Contamination by other substances
- Poor training and improper procedure
- Errors made down the chain of custody
Can you refuse a breathalyzer if not driving?
If you are not operating a vehicle, you are not subject to implied consent laws and can therefore refuse a breathalyzer without facing administrative penalties. However, a police officer likely won’t ask you to take a breathalyzer unless they suspect that you were driving and have evidence to prove it.
Can you refuse a breathalyzer if under 21?
No. Because Texas has a zero-tolerance policy toward underage drinking and driving, minors are subject to the same penalties that an adult would face for breathalyzer refusal.
Continue reading: Can a minor get a DWI in Texas?
Can you refuse a breathalyzer and request a blood test?
Although we’ve laid out some scenarios in which you might prefer to take a blood test instead of a breath test, police officers are not required to comply with your request (unless it is medically necessary).
If you want to take the blood test instead of the breath test, your best bet is probably to refuse the breath test entirely and wait for them to get a warrant for your blood.
Did you refuse or fail a breathalyzer in Houston? Thiessen Law Firm can help.
Weren’t sure if you could refuse a breathalyzer test and bungled your interaction with a police officer? If you’re facing a license suspension as a result of breathalyzer refusal or if you’re facing full-on DWI charges, Thiessen Law firm can help.
At Thiessen Law Firm, we have extensive experience helping the good people of Houston successfully overcome drinking and driving-related charges in court. Mark Thiessen himself has successfully achieved over 100 Not Guilty verdicts and thousands of dismissals for his clients, making Thiessen Law Firm the go-to law firm for DWI cases in Houston.
We know how to take complex DWI cases to court and win them. Call Mark Thiessen and Thiessen Law Firm today at (713) 864-9000 or contact us online to start defending your future.
More Helpful Articles by Thiessen Law Firm:
- DWI with CDL: Can I get a CDL with a DWI?
- How to Avoid Administrative License Revocation
- What Happens at an ALR Hearing in Texas?
- Is a DWI a Felony in Texas?
- How to Win a DWI Trial