Procedural Mistakes in DUI Arrests: What It Could Mean for Your Case in Illinois

What Happens When Police Don’t Follow the Rules During a DUI Arrest in Chicago?

Every day, drivers in Chicago are pulled over on suspicion of driving under the influence. Police officers patrol major roads like Lake Shore Drive, I-90, and I-55 looking for behavior that might signal impaired driving. When they initiate a stop, what happens next can change someone’s life for years to come. But what if the officer doesn’t follow the law? In Illinois, failure to follow DUI arrest procedures can mean the entire case is flawed.

In Illinois, a DUI charge falls under 625 ILCS 5/11-501. This law prohibits operating a motor vehicle while impaired by alcohol, drugs, or intoxicating substances. A first or second DUI is usually charged as a Class A misdemeanor, which can result in up to a year in jail and fines up to $2,500. A third DUI, or a DUI involving injuries, minors, or a revoked license, can be elevated to a felony, carrying multiple years in state prison.

DUI cases begin with a law enforcement investigation. Officers must have reasonable suspicion before pulling someone over. If they stop you without that legal basis, everything that follows—the questioning, the field sobriety tests, and even the arrest itself—could be thrown out in court.

For instance, an officer who stops a driver simply for exiting a bar late at night has no legal grounds to justify the stop. If there’s no erratic driving, broken taillight, or traffic violation, there’s no reasonable suspicion. If your case started like that, your attorney may have a solid motion to suppress.

Our Chicago Criminal Lawyer Blog includes numerous case examples where illegal traffic stops led to suppressed evidence and dismissals. These cases demonstrate how technical DUI laws are in Illinois and why procedure matters.

Common Procedural Errors in DUI Arrests and Why They Matter

The police do not have unlimited authority. The law demands that DUI arrests follow specific protocols designed to protect the public and ensure fairness. When officers skip steps or make legal mistakes, your defense attorney can challenge the entire case.

Here are just a few procedural missteps that often occur in DUI arrests:

• Field sobriety tests that are not administered in accordance with NHTSA (National Highway Traffic Safety Administration) standards
• Chemical tests that are performed on uncalibrated machines
• Improper observation periods before a breath test is given
• Arrests made before probable cause is clearly established
• Failure to advise suspects of their Miranda rights before questioning
• Incomplete or inconsistent police reports

In one case handled by our office, a client was stopped on the Near West Side for an alleged improper lane usage. The officer claimed the driver slurred their words and smelled of alcohol. But bodycam footage showed the driver speaking clearly and walking without difficulty. Even more importantly, the officer admitted under oath that he did not observe any lane violations—he just “had a hunch.” We successfully argued that the traffic stop lacked legal basis, and the court threw out all evidence.

Mistakes like these are not uncommon. In Illinois, once a court finds that the police did not follow lawful procedures, the consequences for the prosecution can be significant. Suppressed evidence can mean the difference between conviction and dismissal.

Our firm regularly challenges DUI arrests based on these types of violations. We also publish helpful content at ChicagoCriminalLawyer.pro to explain how Illinois courts evaluate officer conduct and evidence collection.

What You Risk Without the Right Legal Help

Some people assume that a DUI is not a big deal. But the penalties in Illinois can be life-changing. A misdemeanor DUI carries potential jail time, license suspension, mandatory alcohol education, and steep fines. More serious cases may involve felony charges, including:

• DUI with no valid license or insurance (Class 4 felony)
• DUI causing serious bodily harm (Class 4 or Class 2 felony depending on injury)
• DUI with a child passenger (Class 2 felony)

Even if you avoid prison, a conviction will appear permanently on your criminal record. Illinois does not allow DUI convictions to be expunged or sealed. That means future employers, landlords, and schools can see your conviction forever.

On top of criminal penalties, your license will likely be suspended. If you refused chemical testing, you face a statutory summary suspension under Illinois’ implied consent law. That suspension can be fought, but you must request a hearing within 90 days of your arrest.

A criminal defense attorney will guide you through that process. They will investigate whether the arresting officer followed the law and whether the evidence collected against you is legally valid. The sooner your attorney begins working, the more options you have to avoid harsh penalties.

Our Legal Strategy When Defending DUI Cases in Cook and Surrounding Counties

We take a methodical approach when representing clients accused of DUI in Chicago and surrounding areas. First, we analyze the traffic stop. Did the officer have reasonable suspicion to pull you over? If not, we file a motion to suppress all evidence obtained afterward.

Second, we review the administration of field sobriety tests. Were the instructions clear? Were the tests administered in a well-lit, flat area? Did the officer account for your medical conditions, age, or weight? If not, those test results may be unreliable.

Next, we examine the results of chemical tests. Breathalyzers must be maintained and calibrated regularly. Officers must also observe you for 20 minutes before administering the test to ensure nothing affects the reading. If these steps were skipped, your BAC (blood alcohol content) results can be called into question.

Finally, we prepare to take your case to trial if necessary. In court, we cross-examine the officer, present video or witness evidence, and argue that the state has not met its burden of proof. We never recommend pleading guilty unless we have thoroughly reviewed every legal avenue for dismissal or acquittal.

Many of our clients are professionals, commercial drivers, or parents who cannot afford the consequences of a DUI conviction. We tailor our strategy based on your unique circumstances and fight aggressively to protect your record and your freedom.

Call The Law Offices of David L. Freidberg Today

Call Now – The Law Offices of David L. Freidberg Is Ready to Help

If you’ve been charged with DUI in Chicago and have a medical condition that may have impacted your arrest or test results, call The Law Offices of David L. Freidberg for a free 24/7 consultation.

If you were arrested in Chicago for DUI, protect your future by contacting The Law Offices of David L. Freidberg. We have decades of experience handling DUI cases in Illinois. Our firm is available 24/7 to provide the legal defense you deserve.

Contact us today at (312) 560-7100 or toll-free at (800) 803-1442 for a free consultation. We’re available 24/7 to serve clients throughout Illinois, Cook County, DuPage County, Will County, and Lake County.