Tactics to Discredit Evidence in Illinois DUI Cases

In Illinois, battling a DUI charge involves not just understanding the law but strategically challenging the evidence presented by the prosecution. This is particularly crucial when it comes to breathalyzer results and field sobriety tests, which are commonly used as primary evidence of impairment. Experienced DUI defense attorneys use a variety of techniques to question the validity of this evidence, aiming to protect their clients’ rights and achieve the best possible outcome.

Challenging Breathalyzer Evidence

1. Questioning Calibration and Maintenance

Breathalyzers must be precisely calibrated and regularly maintained to ensure accurate readings. Defense attorneys will scrutinize maintenance logs and calibration records to find lapses in protocol. If a device was not properly calibrated according to the manufacturer’s specifications or state law requirements, the results can be argued as unreliable.

2. Highlighting Operator Errors

The accuracy of a breathalyzer test is also dependent on the operator’s adherence to strict procedural guidelines. Attorneys often question whether the law enforcement officer conducted the test correctly and whether they had the proper training. Any deviation from standard operating procedures can be grounds to dismiss the evidence.

3. Analyzing Environmental and Medical Factors

Various environmental factors and medical conditions can skew breathalyzer results. For instance, substances containing alcohol (like certain medications or mouthwash) can result in falsely high BAC readings. Similarly, medical conditions such as acid reflux or diabetes can alter breathalyzer results. Defense lawyers will explore these avenues to challenge the breathalyzer evidence presented.

Discrediting Field Sobriety Tests

1. Critiquing Test Conditions

Field sobriety tests (FSTs) must be conducted under specific conditions to be considered valid. Defense attorneys will evaluate conditions such as lighting, weather, and road surface to argue that the environment was not conducive for a fair test. For example, performing an FST on an uneven surface could unfairly impact a suspect’s performance.

2. Questioning Officer Conduct and Test Administration

The subjective nature of FSTs allows for significant scrutiny. Defense attorneys often challenge the officer’s conduct during the test—whether they provided clear instructions and whether their subjective judgment could have biased the results. Additionally, the physical and mental condition of the accused at the time of testing can affect their performance on FSTs, providing another angle for challenge.

3. Employing Expert Testimony

Defense teams frequently use expert witnesses to undermine the prosecution’s interpretation of FST results. These experts can provide insights into how various non-alcoholic factors could mimic the signs of intoxication or how nervousness and fatigue could affect a suspect’s performance.

Strategic Use of Scientific Evidence

Advanced scientific critiques of the methodologies used in DUI testing form a cornerstone of challenging DUI evidence. Defense attorneys may present research that questions the reliability of the technology used in breathalyzers and FSTs or highlight newer studies that could demonstrate inherent flaws in these tests.

Legal Precedents and Case Law

Utilizing precedents where evidence was successfully challenged under similar circumstances is another tactic. Lawyers will reference previous cases where breathalyzer results or FST evidence was thrown out due to procedural errors, lack of probable cause, or other violations to bolster their defense.

Successfully challenging DUI evidence requires a deep understanding of both the science behind the tests and the legal frameworks that govern their administration. In Illinois, where DUI convictions can carry significant penalties, having an adept attorney who can effectively dispute the validity of the evidence is crucial.

Contact The Law Offices of David L. Freidberg 24/7/365 at (312) 560-7100 or toll-free at (800) 803-1442 For Your FREE Consultation

If you are facing criminal charges, don’t face it alone. Contact The Law Offices of David L. Freidberg for skilled legal assistance. With decades of experience and a commitment to protecting your rights, we offer a free consultation 24/7 at (312) 560-7100 or toll-free at (800) 803-1442. We serve clients throughout Chicago, Cook County, DuPage County, Will County, and Lake County in Illinois. Let us help you navigate the legal system and fight for your future.