Police officers in Indiana cannot stop a driver or make an arrest for operating while intoxicated (OWI) without evidence. Before charges are filed, officers must follow a process that builds evidence step by step.
This process usually begins with a traffic stop and may include officer observations, field sobriety testing, and chemical testing. Each stage is meant to determine whether a driver may be impaired by alcohol or drugs.
For drivers in Indianapolis and across Indiana, understanding how police investigate drunk driving can help explain how an OWI case begins and what evidence prosecutors may rely on.
Reasonable Suspicion and Traffic Stops in Indiana OWI Investigations
Police must first have reasonable suspicion to stop a vehicle. Reasonable suspicion means the officer believes a traffic violation or unsafe driving behavior occurred.
During suspected drunk driving cases, officers often rely on behaviors such as:
- Swerving or drifting between lanes
- Running a stop sign or traffic light
- Driving significantly below or above the speed limit
- Sudden or erratic braking
An officer may also stop a vehicle for a normal traffic violation, such as failing to signal or having an expired license plate. While speaking with the driver, the officer may begin looking for signs that alcohol or drugs may be involved.
Common observations that may lead to further investigation include the smell of alcohol, slurred speech, bloodshot eyes, or difficulty responding to questions.
Field Sobriety Tests Used by Indiana Police
If an officer believes impairment may be present, they may ask the driver to perform standardized field sobriety tests. These tests are designed to help officers decide whether there is probable cause to make an OWI arrest.
The most common field sobriety tests used during Indiana traffic stops include:
- Horizontal Gaze Nystagmus (HGN) – the officer watches eye movement while the driver follows an object
- Walk-and-Turn Test – the driver takes heel-to-toe steps along a straight line
- One-Leg Stand Test – the driver balances on one foot for a short period
Officers look for specific clues during these tests that may suggest impairment. The results may later appear in police reports and court testimony.
Breath Tests and Chemical Testing in Indiana OWI Cases
When field sobriety testing leads an officer to believe a driver is intoxicated, the officer may make an arrest and request chemical testing.
Indiana’s implied consent law allows police to request an evidentiary breath test after a lawful OWI arrest. The test measures the driver’s blood alcohol concentration (BAC).
In Indiana, drivers age 21 and older may face OWI charges if their BAC reaches 0.08% or higher. Higher readings may lead to enhanced penalties.
Refusing a chemical test may result in a driver’s license suspension, even if a conviction does not occur.
Charged With OWI After a Traffic Stop in Indianapolis?
If you were arrested for drunk driving after a traffic stop, it is important to review how the investigation was handled. Issues involving the traffic stop, field sobriety tests, or chemical testing may affect the evidence used in court.
Hayes Law Office has more than 20 years of experience defending drivers facing OWI and DUI charges in Indianapolis and throughout Indiana. Our firm carefully reviews every part of the investigation to protect our clients’ rights.
If you are dealing with an OWI charge, contact Hayes Law Office today to discuss your case and learn what defense options may be available.
