Chicago Criminal Lawyer Blog
Getting pulled over in Chicago can be a nerve-wracking experience, especially if the officer suspects you’ve been drinking. You may think you’re just answering a few questions or going through routine checks, but from the moment the lights flash behind you, law enforcement is already building a case. Their goal is to collect as much evidence as possible to justify a DUI arrest. But what many people don’t realize is that DUI evidence—especially in Illinois—is often flawed, incomplete, or misinterpreted.
At The Law Offices of David L. Freidberg, we defend people in Chicago and the surrounding counties who’ve been charged with DUI based on questionable police tactics and unreliable evidence. Here’s what law enforcement looks for—and how we challenge it.
Why Every Detail Matters in a DUI Arrest
In Illinois, DUI is charged under 625 ILCS 5/11-501, and the law covers more than just alcohol. You can be arrested for driving under the influence of drugs, prescription medication, or any substance that impairs your ability to drive safely. That includes marijuana—even if you’re a medical card holder.
There are two main ways you can be charged:
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Driving with a BAC of 0.08 or higher
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Driving while impaired by alcohol or drugs, regardless of BAC
Most first and second DUIs are charged as Class A misdemeanors. A third DUI, or one involving a crash, injury, minor passenger, or lack of insurance or a valid license, can be charged as a felony under 625 ILCS 5/11-501(d). These serious charges bring prison time, steep fines, and long-term license revocation.
But to convict you, police and prosecutors must have evidence—and that evidence starts accumulating long before you step foot in a courtroom.
What Police Are Trained to Look For During a DUI Stop
Officers are trained to scan for signs of impairment from the moment they make contact with a driver. Most of what they rely on is subjective, which makes it vulnerable to challenge in court.
Here’s what they look for and how it can be used against you:
Your Behavior at the Window
When an officer approaches your car, they’re paying attention to your speech, how you hand over your license, whether your hands are shaking, whether your eyes appear glassy, and if there’s any odor of alcohol or cannabis.
How You Perform on Field Sobriety Tests
These include standing on one leg, walking heel-to-toe, and following a pen with your eyes. While these are standardized by NHTSA, they are not foolproof. Poor road conditions, fatigue, injury, or nervousness can lead to poor results.
Preliminary Breath Test (PBT)
This roadside breath test is used to estimate BAC. Although not admissible in court to prove guilt, it gives officers probable cause for an arrest.
Statements You Make
Officers may ask if you’ve been drinking. What seems like a casual question is really an evidence-gathering tactic. Anything you say can and will be used against you. Even saying you “had a couple drinks” gives them a reason to continue the DUI investigation.
Dashcam and Bodycam Recordings
This video footage can help or hurt you. Officers may rely on it to support their claims—but if it contradicts their report, it can be powerful evidence for the defense.
Learn more about how the DUI process unfolds at:
https://www.chicagocriminallawyer.pro
Chemical Testing: Not as Accurate as You’d Think
If you’re arrested, you’ll likely be taken to the station for a breathalyzer or to a hospital for blood or urine testing. These tests are used to measure alcohol or drug levels in your system. However, these tests are not infallible.
Breath Tests
These machines require strict maintenance and calibration. A single mistake in calibration can throw off results. Additionally, health conditions like acid reflux or certain diets can affect BAC readings.
Blood and Urine Tests
These are typically used in drug-related DUIs. But they test for the presence of substances, not necessarily impairment. For instance, marijuana can stay in your system for days or weeks after use.
Refusal to Test
Under Illinois’s Implied Consent Law (625 ILCS 5/11-501.1), refusing to submit to chemical testing after arrest leads to a statutory summary suspension of your driver’s license—12 months for a first offense, 36 months for a second.
But here’s what many people don’t realize: refusing the test can limit the prosecution’s ability to prove intoxication.
For a closer look at how chemical testing plays out in DUI cases, visit:
https://www.chicagocriminallawyerblog.com
The Criminal Case Timeline in Illinois
After arrest, your DUI case will move quickly through the court system. Each stage presents an opportunity to defend yourself—but only if you have an experienced attorney by your side.
Initial Hearing
You’ll appear before a judge who will set bond and your next court date. If your license is subject to a statutory summary suspension, we will immediately request a hearing to challenge it.
Discovery and Investigation
This is where we request the evidence against you—videos, police reports, lab results, and more. If anything is missing or doesn’t match the officer’s story, it may be suppressed.
Motion Hearings
We may file a motion to suppress evidence based on an illegal stop, improper testing, or mishandled procedures. These hearings often determine whether your case can move forward.
Trial or Plea Negotiation
We prepare for trial in every case, but if the facts warrant a negotiated outcome, we push for a resolution that avoids jail time, license loss, and a permanent record.
Without a defense attorney, most people have no idea how to challenge the evidence—or even what evidence exists.
Real Case: False Positive on Breath Test Leads to Dismissal
We represented a client arrested after leaving a concert near United Center. He was stopped for failing to signal. The officer said he “reeked of alcohol” and performed poorly on FSTs. A breath test at the station showed a 0.09 BAC.
Our investigation revealed that the officer did not follow required observation periods before the test. Our client had used mouthwash, which can trigger false positives. We also obtained video showing no signs of impairment. The judge suppressed the breath test, and the case was dismissed.
Cases like this are common—when you know where to look.
Challenging the Evidence in Your DUI Case
DUI cases often come down to how the evidence was gathered and whether your rights were respected. Common ways we challenge DUI evidence include:
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Unlawful Traffic Stops
Police must have a valid reason to stop you. If they didn’t, the entire case can be thrown out. -
Improper Field Sobriety Test Administration
If the officer skipped steps or failed to explain the instructions, the results can be discredited. -
Breathalyzer Inaccuracy
Calibration logs, operator certification, and observation protocols are all required. A mistake in any of these areas can render the result inadmissible. -
Medical and Environmental Factors
Health conditions, medications, and even the shoes you were wearing can affect test results or behavior during a stop.
FAQs: What You Need to Know About DUI Evidence in Illinois
Is it better to refuse a breathalyzer test?
Refusing can lead to a longer license suspension, but it also means prosecutors may have less evidence against you. It’s a tradeoff that depends on your situation.
Can video evidence help my case?
Yes. Video can contradict officer testimony, show clear performance on tests, or prove that the stop was unjustified. We review all available video in every case.
Can I be arrested for DUI without a BAC test?
Yes. Officers can arrest based on their observations alone. But without chemical evidence, the prosecution’s case becomes much weaker.
What is the statutory summary suspension?
It’s an automatic driver’s license suspension triggered by failing or refusing chemical testing. You have only 90 days to contest it.
Can I still be charged with DUI if I was under the legal limit?
Yes. If police believe you were impaired, they can charge you even if your BAC was below 0.08. That’s why your defense needs to be built carefully.
You Need a Defense Lawyer Who Knows DUI Evidence Inside and Out
Police and prosecutors are trained to build DUI cases—but that doesn’t mean they’re always right. The evidence can be flawed, the procedures mishandled, and your rights ignored. The only way to level the playing field is with a skilled attorney who knows how to find the weaknesses in their case.
At The Law Offices of David L. Freidberg, we’ve spent decades defending clients against DUI charges across Chicago, Cook County, DuPage County, Will County, and Lake County. We know what works, and we know what doesn’t.
Call The Law Offices of David L. Freidberg Today
If you’re under investigation or facing charges, act now. The prosecution is already building a case. You deserve a defense that’s prepared to challenge the legality of every move law enforcement made.
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.
You don’t have to face this alone—we’re here to fight for you.
