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  • Jim Medley

To Use or Refuse a Breathalyzer

Many people ask whether they should provide a BAC chemical sample or refuse to comply with this request, and there are two very legitimate sides to this argument.

Statistics vary by county, but the conviction rate in breath test cases is usually about 85 percent and 45 percent in refusal cases. So, many argue, taking a breath test essentially gives the prosecutor the evidence necessary to secure a conviction, and the state does not need your help in this area.

On the other hand, there’s an old saying that when you dig yourself into a hole, your first order of business is to stop digging. Since the drivers’ license suspension period is about twice as high in refusal cases, and the refusal is used against the defendant in court, others argue that nothing good comes from a test refusal and therefore it is a good idea to take one.

Of course, during certain “no-refusal” enforcement periods, peace officers take this matter out of the defendant’s hands, because they obtain search warrants for blood draws if the defendant refuses consent.

Breathalyzer Reliability

Sometimes, there is also a middle ground. It may be possible to say something like “I refuse to take a Breathalyzer test but I will consent to a blood draw.” Since police officers rarely bother to obtain search warrants for blood draws, the jury may get the impression that the officers believed the evidence was so weak, they did not want to test the defendant.

There’s a larger issue as well, the Breathalyzer’s reliability. The device purges the defendant’s breath sample, so there is no way to scientifically test the specific results. As a result, the same questions that have plagued the Breathalyzer since its invention in the 1950s still persist.

  • Mouth Alcohol: If the defendant burps or belches even a little bit, the additional mouth alcohol artificially inflates the breath alcohol reading, which affects the translation to blood alcohol content (BAC).

  • Acetone: Many people, including diabetics and smokers, have high levels of this chemical, which is a by-product of the body’s energy production. The Breathalyzer normally registers acetone as ethanol, since the two have similar chemical compositions.

  • Unabsorbed Alcohol: Most people metabolize alcohol at the rate of .01 BAC per hour, so if the defendant had anything to drink in the last hour, the Breathalyzer result may be artificially high.

If the defendant consents to a blood test, a defense attorney can have the sample professionally analyzed, and that analysis is often markedly different from the one that occurs at a crime lab.

Rely On an Experienced Attorney

The chemical sample step is an important phase in a DWI case. For a free consultation with an experienced criminal defense lawyer in Houston, contact Jim Medley Defense Lawyer.

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