Law Offices of Swanton & Frederick
Defending Your Rights, Protecting Your Future

Resources Content


Should I take the blood or breath tests if I am stopped for a DWI?

One of the most common questions that we get in our practice, and frankly, in everyday conversations with our friends and acquaintances is: "Should I take the blood or breath tests if I am stopped for a DWI?" The answer is probably more complicated than you want to hear or read about.

Before answering that question, let's talk about a couple of important related matters. Remember, the Government/State always has the burden of proof in a criminal matter. It has to prove someone is guilty beyond a reasonable doubt. "Intoxication" in Texas is defined as having a breath or blood test level of .08 or greater at the time of driving or not having the normal use of your mental or physical faculties because of the introduction of alcohol or drugs into your body. If you take the test and it shows that you have a BAC (Blood Alcohol Concentration) level at or above .08 at the time of driving, then you are at or above the level that is presumed to be a level of intoxication. By taking the test, you have given the Government evidence to use against you in the case. Even if you are below the .08 level you could still be charged with a DWI under the theory that you have lost the normal use of your mental or physical faculties and the test would be used to show some alcohol was introduced into your body.

Police Lights on as police car drives through downtown

A breath test machine is not infallible. It is a machine made and operated by human beings and as we all know, human beings make mistakes from time to time. Experts tell us that there are a number of factors that can affect the test results of Intoxilizer testing machines and skew those results to show higher BAC amounts than they should. Generally speaking, blood test results are considered to be more reliable but even those tests can be adversely affected by a number of variables.

Our general advice is that you should not voluntarily take a breath or blood test if you find yourself in the unfortunate position of being pulled over for a DWI. If you know for a fact that there is absolutely no alcohol or drug in your body and you are absolutely sure that the machine testing your breath or blood is going to be accurate and that the individual taking your breath or blood has been properly trained to do so, then we would understand why you would go ahead and take the test. It is difficult to imagine a person finding themselves in this specific situation though. Our advice is that it is wiser to politely decline the request to take these tests.

There are a number of issues associated with breath/blood tests and DWIs that are too complicated to set forth in this short format. There are many rules about a number of different matters including, but not limited to: search warrants for blood under some circumstances, license suspension time frames, surcharges, offense levels and potential punishments that can all be affected by the refusal or results of a breath/blood test. We would be happy to discuss these issues if you want to talk to us. Just give us a call.

Jeremy Bush