slope detector

Being found guilty of DWI in the state of Texas is extremely serious. And it can come with some pretty disastrous consequences. That is why it is important to know how to defend yourself against your arrest charges. If you have failed a breathalyzer test, that does not automatically mean that you will be found guilty. There are some things about a breath test that can make them unreliable. Because some breathalyzers use a “slope detector” and some don’t, there are instances where an argument can be made about the reliability of your positive test.

What Is the Slope Detector in a Breath Test?

One reason that a breath test might be rendered unreliable is due to the slope detector. When you breathe into a breathalyzer, the device is supposed to detect when the sample is a deep lung breath. This is how it distinguishes the alcohol level in your system from the alcohol level in your mouth. Although most modern breathalyzer tests use slope detection, there are still some in operation that do not. Newer devices have something called an infrared slope detection system that can distinguish a mouth sample from a lung sample. These breathalyzer tests estimate that the first two-thirds of the sample is not a fair concentration and are, therefore, discarded.

What if a Breath Test Doesn’t Have a Slope Detector?

It is imperative to know what model of breathalyzer was used to conduct the breath test. If your test was performed on a model that does not have the slope detector built-in, then it might be possible to argue that the test results are not reliable, and are, therefore, inadmissible as proof of your intoxication. When there is not a slope detector built-in, it is the officer’s duty to perform a test to determine whether the sample was a lung or a mouth sample. Even if the breathalyzer does have a slope detector installed, issues can still arise if the detector is inadequate to detect the difference between a lung and a mouth breath.

Know Your Rights

When you are pulled over for suspicion of DWI in Texas, you are required to submit to a breathalyzer test. If you do not, then you will face arrest charges and an automatic suspension of your license. Even if you take the test and fail, there are instances in which you can argue your innocence. Depending on what model was used to test your breath, the slope detector, or lack thereof, might be an issue.

There are many factors that can affect breathalyzer reliability. Before you stand trial for your DWI arrest, it is imperative to know all the issues regarding the case built against you, including the model of the breathalyzer test used. If you need a DWI/DUI lawyer to build your winning defense, contact Stephen T. Bowling today.

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