Local DUI Laws

What Leads to an OWI Arrest in Michigan?

In Michigan, impaired driving is charged under the legal term OWI—Operating While Intoxicated. While most people associate an OWI arrest with failing a breathalyzer, the process starts much earlier. A Michigan OWI arrest isn’t typically the result of a single factor; it often stems from a combination of observed behaviors, roadside interactions, and chemical test results.

Understanding what actually triggers an OWI arrest is key for drivers in Michigan. From the moment a traffic stop begins, law enforcement officers are trained to observe, evaluate, and document evidence of impairment. These decisions are based on a combination of visual cues, speech patterns, coordination, and BAC test results.

This post explores the common signs that lead to OWI arrests in Michigan—from initial traffic stops to field sobriety tests and chemical testing. It offers a neutral, educational overview of what police look for, how arrests unfold, and how the process fits within Michigan’s larger OWI law framework.

Driving Behaviors That Lead to OWI Stops in Michigan

Before an OWI arrest can occur, there must be a legal reason for the traffic stop. In Michigan, officers often initiate a stop after noticing erratic or unsafe driving behaviors that suggest possible impairment. These might include:

• Drifting between lanes
• Driving too slowly or speeding
• Braking unpredictably
• Failing to signal
• Ignoring traffic signs or signals
• Straddling the center line

These actions don’t prove impairment, but they do provide reasonable suspicion for officers to investigate further. Once the vehicle is stopped, the officer’s observations continue—and everything from a driver’s demeanor to the smell of alcohol can become part of the official record.

Michigan law does not require an officer to witness a crash or dangerous event to initiate an OWI stop. Even minor traffic violations can prompt a check for signs of intoxication, especially during high-enforcement periods like holidays or late-night hours.

Interaction with the Driver: Key Observations

Once the vehicle is stopped, Michigan law enforcement officers focus closely on the driver’s behavior, appearance, and responses. This includes basic interactions such as:

• Difficulty answering simple questions
• Slurred or mumbled speech
• Bloodshot or glassy eyes
• Smell of alcohol or marijuana
• Slow or erratic motor movements
• Confusion when asked for license and registration

These observations play a major role in deciding whether further investigation is warranted. Michigan officers are trained to document their impressions carefully, as they can support an OWI charge even if chemical testing is inconclusive or refused.

Importantly, drivers are not required to answer questions beyond providing identification, but refusal to cooperate in other ways—like stepping out of the vehicle—can escalate the situation. Even if a driver believes they’re not impaired, poor communication during a stop can increase the likelihood of further testing.

Field Sobriety Testing: A Standard OWI Protocol

In Michigan, if a law enforcement officer suspects impairment, the next step is usually standardized field sobriety testing (SFST). These are physical and cognitive tests designed to assess coordination, balance, and attention. Common field sobriety tests used in Michigan include:

• The Horizontal Gaze Nystagmus (HGN) test
• The Walk-and-Turn test
• The One-Leg Stand test

These tests must be administered according to strict guidelines, but they are subjective by nature. An officer’s interpretation of a driver’s performance can lead directly to an arrest—even if no chemical test has been conducted yet.

While these tests are voluntary under Michigan law, declining to participate may prompt the officer to rely on other evidence, such as observations or preliminary breath tests, to make an arrest decision. It’s also important to note that performance may be influenced by medical conditions, fatigue, or even nerves, which can complicate the evaluation.

Preliminary and Chemical BAC Testing in Michigan

If an officer has probable cause, they may ask the driver to submit to a Preliminary Breath Test (PBT) at the roadside. While the PBT is not as accurate as later chemical testing, it provides an immediate estimate of BAC (Blood Alcohol Content), which can inform an arrest decision.

Under Michigan’s implied consent law, drivers who are arrested for OWI must submit to official chemical testing, usually administered at a police station. This test, commonly a Datamaster breathalyzer, is used to formally determine whether the driver’s BAC is over the legal limit of 0.08% for most drivers, or 0.02% for those under 21.

Refusing the post-arrest chemical test can result in automatic license suspension, even without a conviction. It’s separate from the PBT refusal, which generally results in a civil infraction. Many OWI arrests occur even before chemical test results are in, based solely on officer observations and field tests.

Impairment Without Alcohol: Drug-Related OWI Arrests

Michigan’s OWI laws apply to more than just alcohol. A driver can be arrested if they are suspected of being impaired by prescription medications, marijuana, or illegal drugs, even in the absence of alcohol. Officers trained as Drug Recognition Experts (DREs) may be called in to assess drivers in these situations.

Common signs of drug impairment include:

• Slow reaction time
• Dilated or constricted pupils
• Rapid speech or extreme fatigue
• Confused behavior

If drug impairment is suspected, officers may require a blood or urine test to detect the presence of substances. Michigan law treats drug-based OWI cases just as seriously as alcohol-based ones. A driver does not need to be over a particular BAC threshold to be arrested—they simply need to be impaired by any substance that affects their ability to drive safely.

This aspect of OWI enforcement is increasingly relevant as marijuana use becomes more common and prescription medications often have side effects that can impair driving ability.

Refusal and Resistance During a Traffic Stop

While drivers have rights during a traffic stop, refusal to comply with certain procedures can quickly escalate the situation. In Michigan, refusing to exit the vehicle when asked, resisting a search, or becoming argumentative may give officers further justification for an OWI arrest.

It’s also important to understand the distinction between preliminary tests (which are usually voluntary) and chemical tests (which become mandatory after arrest). Many drivers mistakenly assume they can refuse all tests without penalty, but under Michigan’s laws, refusal of a post-arrest chemical test can result in a one-year license suspension, even for a first offense.

Behavior during the stop—such as failing to follow instructions, appearing hostile, or attempting to leave—can also lead to arrest or additional charges. Officers in Michigan are given discretion in how to respond, and non-cooperative behavior often leads to a more aggressive enforcement response.

OWI Arrest Procedures and Documentation

Once enough evidence has been collected, an officer may proceed with placing the driver under arrest for OWI. In Michigan, this involves being taken into custody, transported to a local station, and undergoing further chemical testing. The arresting officer will complete a detailed incident report, noting:

• The reason for the initial stop
• Observations made during the interaction
• Results of field sobriety tests
• BAC test results (if any)
• Any driver statements or behaviors

This documentation becomes the foundation for any future legal proceedings. Even if a driver is later found not guilty, the arrest record remains. Additionally, some OWI arrests include immediate administrative penalties, like a temporary license suspension.

Understanding that every phase of the stop is being observed, recorded, and documented helps illustrate how easily an OWI arrest can be triggered under Michigan law—even when a driver believes they’re in control.

FAQ: OWI Arrest Triggers in Michigan

What behavior causes an officer to suspect OWI in Michigan?
Erratic driving, slurred speech, poor coordination, or the smell of alcohol are all common cues officers look for during a stop.

Is it legal to refuse a breath test during a Michigan OWI stop?
Refusing a preliminary breath test is a civil infraction. Refusing a chemical test after arrest results in a license suspension.

Are field sobriety tests required by law?
No. In Michigan, these tests are voluntary, but refusing them may not prevent arrest if other signs of impairment exist.

Can you be arrested for OWI without a breath test?
Yes. If an officer has sufficient evidence based on behavior, observations, and field tests, they may proceed with an arrest.

What substances can lead to an OWI arrest in Michigan?
Alcohol, marijuana, prescription drugs, and illegal substances—all can be grounds for an OWI arrest if impairment is evident.

Does Michigan use dash cams or body cams during OWI stops?
Many police departments in Michigan use both, and footage can be used in documenting the stop and arrest process.

What happens after an OWI arrest?
The driver is taken into custody, tested (if not already), and booked. A hearing or arraignment is usually scheduled shortly after.

Conclusion

OWI arrests in Michigan can be triggered by a wide range of behaviors and observations. From the initial traffic stop to the arrest itself, officers follow a multi-step process rooted in Michigan’s impaired driving laws. Understanding what they look for can help drivers make informed, legal-conscious choices.

To learn more about Michigan’s impaired driving laws and how charges are handled, explore our full guide on how OWI laws work.

For a deeper look at the warning signs and behaviors that most often result in an arrest, check out our mini-guide on what triggers an OWI arrest during a traffic stop.