If you are stopped in Austin, Texas for a DWI, you can be charged with this offense under Texas law if a breath or blood test is administered and you show a blood alcohol concentration (BAC) of 0.08 percent or higher. But what happens when your driving behavior does not accurately reflect a 0.08 percent BAC? In other words, if your behavior does not suggest alcohol impairment, can you still face DWI charges?

As an Austin DWI attorney, I typically refer to these scenarios as “disconnect” cases, or cases in which there is a clear disconnect between the driver’s BAC and his or her perceived level of impairment. In some situations, the BAC might be low—well below the legal limit—yet the person exhibits signs of driving while intoxicated. In other scenarios, the driver may appear completely sober but may have a BAC at or above 0.08 percent. When there is a disconnect case, it is extremely important to work with me and my law office to show that the BAC results are not reliable. The following are a few ways we can show that your BAC reading was inaccurate.

Defective BAC Testing and Equipment Produces Inaccurate Results

If you were not drinking alcohol (or only had a single drink) but allegedly drove with a BAC of 0.08 percent or higher, it is possible that there was a problem with the testing or with the equipment used to perform the test. There are many different ways in which a BAC test can be inaccurate. As a publication from the National Highway Traffic Safety Administration (NHTSA), there are many reasons for an inaccurate BAC due to defective testing or equipment, including but not limited to:

Ethanol Produced By Other Means

Disconnect cases often result from other conditions or situations that produce ethanol in the body, leading to an inaccurate BAC test result. As an article in the journal Pharmacology explains, reactions to ethanol can vary. When ethanol is produced in the body by other means—such as by cold medicines, mouthwashes, and dental work—it can lead to a high BAC reading while the person’s behavior simply does not suggest that she or he is impaired by alcohol. In Texas, law enforcement often looks for some of the following signs of intoxication when making an arrest:

When a person does not exhibit any of these signs yet has a BAC at or above 0.08 percent, there is clearly a disconnect in the case. Likewise, it is easy to imagine how a person might exhibit some of the characteristics due to drowsiness, for example.

In sum, breath and blood tests are not always accurate for a wide variety of reasons, and at the same time, there are numerous explanations for a person having a BAC above the legal limit or showing signs of intoxication when they are not actually impaired by alcohol.