Beating the Breathalyzer in an Illinois DUI Case

If a DUI defendant provides a chemical sample, many defense attorneys essentially raise the white flag of surrender and immediately go into plea negotiation mode. While the conviction rate in test cases is almost twice as high as it is in refusal cases, it is still possible to fight the evidence in chemical test prosecutions and win based on the merits.

It is important to both maintain an aggressive posture in each case and have a reputation for fighting DUIs in court. Even if success at trial is unlikely, these lawyers are able to negotiate better plea agreement settlements than attorneys who retreat into “plea closets.” Word travels fast at the courthouse. Lake County prosecutors quickly learn which attorneys will go to the mat for their clients and which ones will throw in the towel, and they negotiate accordingly.

The Science Behind Illinois Breathalyzer Tests

Nearly all Chicago DUI test cases involve Breathalyzers. Under Birchfield v. North Dakota, police officers must obtain search warrants before they administer blood tests. Moreover, such tests are incredibly time-consuming.

As a side note, it is sometimes a good idea for DUI suspects to refuse a Breathalyzer but agree to a blood test. If officers proceed with the test, so be it. Blood tests are better than breath tests for defense purposes, anyway, because a non-state expert can analyze a blood sample. If the officers do not order a blood test, which is rather likely, jurors may infer that the officers believed the evidence was weak and they were afraid to order a chemical test.

There are two important things to remember about Breathalyzers. First, they do not measure blood alcohol content, which is the law’s requirement. Instead, they measure breath alcohol then use that figure to estimate blood alcohol content. The extra step creates potential for error, as outlined below.

Second, the Breathalyzer’s technology is essentially unchanged since it was introduced in the 1950s as the “drunk-o-meter.” When television sets of that era picked up broadcast signals, the viewer got a bad picture and poor sound quality. The Breathalyzer is basically the same.

Some Breathalyzer Flaws in Chicago

The extra step creates problems for Cook County prosecutors, especially in borderline cases. Some of the specific flaws include:

  • Mouth Alcohol: If the defendant belches or burps within 15 minutes before the test, the results may be off significantly. Officers are supposed to continually monitor suspects for the entire period, but they often turn their heads.
  • Acetone: Certain dieters, along with most smokers and diabetics, have high acetone levels in their bodies. The Breathalyzer falsely reads acetones as ethanol.
  • Unabsorbed Alcohol: If the defendant ingested any alcohol within an hour before the test, the liver has not yet absorbed that alcohol and released it into the bloodstream, so the Breathalyzer’s BAC estimate will be artificially high.

To highlight these flaws, many attorneys partner with chemists or other expert witnesses. In contrast, most Illinois prosecutors call non-degreed Breathalyzer technicians to authenticate the results and speak up for the device.

Contact Aggressive Lawyers

It is possible to fight DUI test cases and win. For a confidential consultation with an experienced criminal law attorney in Schaumburg, contact Glasgow & Olsson.

(image courtesy of Jean Gerber)

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