Signs of Impairment Police Look For During a Traffic Stop

When pulled over by law enforcement, a routine traffic stop can quickly turn into a DUI investigation if the officer suspects impairment. Police officers are trained to observe specific signs of impairment during these stops, looking for clues that suggest a driver might be under the influence of alcohol, drugs, or other substances. Understanding the signs that police look for during a traffic stop can help you protect your rights and avoid unintentionally giving the impression of impairment.

If you’re stopped by the police, knowing what to expect and how to respond can make a significant difference. Here’s what officers are looking for during a traffic stop, the procedures they follow, and why having an experienced DUI attorney is essential if you’re charged with impaired driving.

Common Signs of Impairment Observed by Police

Police officers look for a variety of physical and behavioral signs during a DUI traffic stop. Even innocent actions can be interpreted as signs of impairment if they align with police training and established DUI detection guidelines. Here are the key signs officers observe:

Erratic Driving or Traffic Violations
A traffic stop is usually initiated due to erratic driving behavior or a traffic violation, which can be the first indicator of possible impairment. Police may pull drivers over for weaving between lanes, drifting, speeding, or braking abruptly. These behaviors are commonly associated with impaired driving and can raise an officer’s suspicion.
Odor of Alcohol or Drugs
One of the first things police look for when approaching a driver’s window is the smell of alcohol or drugs. The scent of alcohol on your breath or the smell of marijuana or other drugs can lead officers to suspect impairment and initiate further investigation. This can include questioning about recent consumption and requesting field sobriety tests.
Slurred or Slow Speech
Slurred or slowed speech is often associated with intoxication, and officers pay close attention to how you respond to questions. They may ask simple questions and look for signs of difficulty in responding clearly, interpreting slurred or delayed responses as signs of impairment.
Bloodshot or Glassy Eyes
Bloodshot, watery, or glassy eyes are considered signs of intoxication by law enforcement. Officers are trained to examine a driver’s eyes as an indicator of alcohol or drug use, even though other factors, like allergies or fatigue, can cause similar symptoms.
Disorientation or Confusion
Difficulty following instructions or answering questions can also be interpreted as impairment. Police will observe how you respond to their instructions, such as requests for your license and registration. Struggling to find these documents or becoming easily confused may raise suspicion of impairment.
Physical Appearance and Movements
Officers will look for signs of poor coordination or unusual body movements, such as swaying, fumbling, or unsteady walking. When you exit the vehicle or hand over documentation, police watch closely to see if you appear shaky, unbalanced, or exhibit physical signs of impairment.
Open Containers or Drug Paraphernalia
If an officer spots open alcohol containers or drug paraphernalia in the car, it immediately escalates suspicion. Even if you haven’t consumed alcohol or drugs recently, the presence of these items may lead the officer to conduct field sobriety tests or request a breathalyzer.
Admission of Drinking or Drug Use
In high-stress situations, some drivers unintentionally admit to drinking or using drugs earlier, believing honesty might lead to leniency. However, any admission of alcohol or drug consumption can give police probable cause to investigate further, often leading to field sobriety testing or chemical tests.

Field Sobriety Tests and Their Purpose

If an officer suspects impairment, they may ask you to perform field sobriety tests (FSTs) to gauge your coordination, balance, and cognitive function. These tests are standardized, but they can be difficult even for sober individuals, especially if you’re nervous or physically unsteady. Here are the common field sobriety tests:

Horizontal Gaze Nystagmus (HGN): This test involves following an object, like a pen, with your eyes as the officer moves it from side to side. Officers look for involuntary eye movements (nystagmus), which can be exaggerated by alcohol use.
Walk-and-Turn: The walk-and-turn test requires you to take several steps in a straight line, turn around, and walk back. Officers observe balance, coordination, and whether you can follow instructions.
One-Leg Stand: This test requires you to stand on one leg while counting aloud. Officers check for swaying, using arms for balance, or difficulty maintaining the position.

While these tests are commonly used, they’re not always accurate indicators of impairment and can be affected by medical conditions, age, physical limitations, and even the environment.

Chemical Tests: Breathalyzers, Blood, and Urine Tests

If an officer has probable cause to believe you are impaired, they may ask you to take a chemical test. This can include a breathalyzer test to measure blood alcohol concentration (BAC) or, in some cases, a blood or urine test. In Illinois, if you refuse a chemical test after being arrested for DUI, you face an automatic statutory summary suspension of your license, as outlined under 625 ILCS 5/11-501.1.

It’s important to understand that breathalyzer machines aren’t always accurate, and factors such as medical conditions or mouthwash can lead to false positives. Chemical test results are not foolproof and can be challenged in court, especially if there were issues with the test’s administration or the equipment used.

Your Rights During a Traffic Stop and DUI Investigation

When you’re pulled over and questioned, you have specific rights that can protect you. Knowing these rights can help you handle a traffic stop without compromising your defense.

Right to Remain Silent: You are not obligated to answer questions about your recent drinking or drug use. Politely informing the officer that you would like to remain silent is within your rights.
Right to Refuse Field Sobriety Tests: In Illinois, you can legally refuse to perform field sobriety tests without facing direct penalties. However, refusal may lead to increased suspicion and could result in a chemical test request.
Right to Consult an Attorney: If you are arrested for DUI, you have the right to consult with an attorney. An attorney can advise you on how to respond to police questions and help protect your rights throughout the process.

Why You Need a DUI Defense Attorney if Charged with Impairment

If a traffic stop results in DUI charges, hiring an experienced DUI defense attorney is critical. A DUI conviction can carry severe consequences, including fines, license suspension, increased insurance rates, and potential jail time. Here’s how a DUI defense attorney can help you:

Challenge the Evidence: A skilled attorney will review the evidence, including the results of field sobriety and chemical tests, to identify inaccuracies or procedural errors. Breathalyzers and other testing devices can be faulty, and improperly administered field sobriety tests can skew results.
Scrutinize Police Conduct: Police officers are required to follow strict procedures during traffic stops and DUI investigations. If your attorney discovers that officers didn’t follow proper protocol or violated your rights, they can work to have evidence dismissed.
Negotiate Lesser Charges or Penalties: An experienced DUI defense attorney can negotiate with prosecutors for reduced charges or alternative sentencing, such as probation or community service, particularly if it’s a first-time offense.
Develop a Defense Strategy: A DUI defense attorney will build a strategy tailored to your case, whether it involves disputing test results, questioning police conduct, or highlighting any medical conditions that might explain your behavior.

Call Us For Your Free Consultation

If you or a loved one is facing DUI charges, 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.