The Role of Forensic Labs in DUI Defense

If you are facing charges for driving under the influence (DUI) in Illinois, there are many potential defenses that an experienced attorney will explore. For example, a criminal defense attorney will examine the circumstances surrounding your traffic stop and arrest to ensure that law enforcement officers did not violate your constitutional rights against unreasonable search and seizure. Your attorney may also look into the whether officers performed roadside sobriety tests in the correct manner. One strong defense that many people may not realize is that the police forensic laboratory made an error processing any evidence in your case.

Common Lab Errors

Forensic labs are responsible for processing different kinds of evidence in DUI cases. For example, labs are often charged with properly calibrating Breathalyzer devices and properly reporting Breathalyzer readings. If a lab employee makes a mistake in maintaining, calibrating, or reading a Breathalyzer device, the blood alcohol content (BAC) reading from that device should not be allowed in court as evidence that you were under the influence.

Additionally, if law enforcement officers performed a blood test to determine your BAC, the forensic lab will be responsible for processing your test results. Many mistakes can be made in this process that may cause an inaccurate result of a blood test, including the following:

  • Any unlicensed, untrained, or unauthorized lab employees handling the test sample;
  • Too long of a delay between drawing of the blood and analysis of the sample, which can allow additional alcohol fermentation in the blood sample;
  • Improperly storing the blood sample before it is processed, such as at the wrong temperature or in an unsterile environment;
  • Failing to preserve the blood sample with the correct anticoagulants;
  • Allowing any product with ethyl alcohol to come in contact and contaminate the blood sample;
  • Mislabeling the blood sample, causing possible processing of the wrong sample; or
  • Not preparing a report of the blood test results in a timely fashion, risking possible reporting errors.

The accuracy of BAC test results is extremely important for the evidence to be credible. If there is even the slightest question that a forensic lab made a mistake in processing your Breathalyzer or blood test, a DUI defense attorney can argue that the results of that test should be kept out of court.

BAC test results are often the only piece of concrete evidence the prosecutor has against you in a DUI case. Once that evidence is thrown out by a judge, a prosecutor likely only has the testimony of police officers regarding their observations of your behavior. If an officer testifies that you seemed out of sorts or did not speak clearly, it is always possible that there is another explanation for such behavior, like you were very tired or on certain medications. Even if the BAC test results are not completely thrown out, your defense attorney can still argue that the reading was not accurate or that the blood sample was contaminated. Such an argument can put significant doubt in the mind of a judge or jury.

If you are facing DUI charges, Chicago defense attorney Steven Goldman will build an aggressive defense in your case. Contact Goldman & Associates today for assistance.

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