You can refuse field sobriety tests in Michigan. The roadside walk-and-turn, one-leg stand, and eye-tracking exercises are voluntary, and no Michigan statute imposes a license suspension, fine, or criminal charge for declining them. That is the short answer, and it is the answer most drivers get wrong. The longer answer matters too, because the officer standing at your window has other tools, and the tests you actually cannot refuse without penalty are different tests entirely.
Why the Tests Are Voluntary
Michigan’s Implied Consent Law, codified at MCL 257.625c, is the source of the penalties most drivers have heard about. It applies to chemical tests of breath, blood, or urine administered after a lawful arrest. It does not apply to the physical coordination exercises an officer asks you to perform on the shoulder of the road before any arrest happens. There is no parallel statute making roadside field sobriety tests mandatory, and no automatic license sanction for saying no to them.
That legal reality is straightforward. The practical reality is messier.
What Refusal Actually Costs You in Practice
Declining the tests does not end the encounter. An officer can still arrest you based on other observations: the smell of alcohol, slurred speech, bloodshot eyes, fumbling with your documents, or the driving behavior that prompted the stop in the first place. In People v. Rizzo, a Michigan court confirmed that the smell of alcohol alone provides enough reasonable suspicion to require a driver to step out of the vehicle for field sobriety testing. The officer does not need your cooperation to build a case.
Refusal can also surface at trial. A prosecutor may argue that you declined because you knew you would fail, and officers frequently treat a refusal as one more factor supporting probable cause for arrest. So the legal right to refuse is clear, but the tactical value depends on what the officer already has. If you have been drinking and the officer already smells alcohol, refusing may deprive the prosecution of one category of evidence. If you have not been drinking at all, performing the tests carefully may end the stop faster than a refusal that escalates the officer’s suspicion.
There is no formula. The decision is yours to make in the moment, with the understanding that either choice has trade-offs.
Field Sobriety Tests Are Not the Same as the Breath Test
This is the single most important distinction to keep straight, because Michigan law treats three different tests three different ways.
Roadside Field Sobriety Tests
The physical coordination exercises. Voluntary. No statutory penalty for refusal.
The Preliminary Breath Test (PBT)
Under MCL 257.625a, an officer with reasonable cause to suspect alcohol-impaired driving can require you to blow into a small handheld breath device at the roadside. Refusing the PBT is a civil infraction for most drivers. For operators of commercial motor vehicles, PBT refusal is a misdemeanor punishable by up to 93 days in jail or a $100 fine. The PBT result can be used to establish probable cause for arrest, but its admissibility at trial is limited under MCL 257.625a(2)(b); it generally cannot serve as the primary evidence of your BAC in the prosecution’s case.
The Post-Arrest Chemical Test
After a lawful arrest, the implied consent statute kicks in. This is the formal evidentiary test, usually administered at the station or a hospital, using more precise equipment than the roadside PBT. Refusing this test is where the serious sanctions live:
- A first refusal triggers a one-year license suspension and adds six points to your driving record.
- A subsequent refusal within seven years triggers a two-year suspension and six points.
You have 14 days after receiving notice of the suspension to request a hearing with the Secretary of State. Miss that window and the suspension takes effect automatically. The hearing itself must be scheduled within 45 days of arrest and resolved within 77 days, absent witness unavailability or exceptional circumstances.
The point of laying these three tests side by side: when people ask whether they can refuse “the test,” they often do not know which test they mean. You can refuse the roadside coordination exercises with no direct penalty. You will pay a civil infraction (or worse, if you drive commercially) for refusing the handheld PBT. And you will lose your license for a year for refusing the post-arrest chemical test, whether or not you are ultimately convicted of anything.
What You Would Be Agreeing to if You Say Yes
If you agree to perform field sobriety tests, Michigan officers follow the protocols developed by the National Highway Traffic Safety Administration.1National Highway Traffic Safety Administration. DWI Detection and Standardized Field Sobriety Test SFST Resources Three tests make up the standardized battery.
Horizontal Gaze Nystagmus
The officer holds a pen or fingertip about 12 to 15 inches from your face and moves it slowly side to side, watching your eyes for involuntary jerking. Three specific clues are scored per eye: whether the eye fails to follow smoothly, whether jerking begins before the eye reaches a 45-degree angle, and whether jerking appears at maximum deviation. In People v. Berger, 217 Mich App 213 (1996), the Michigan Court of Appeals held that HGN qualifies as reliable scientific evidence for establishing the presence of alcohol, provided the test was properly administered by a qualified officer. HGN shows the presence of alcohol rather than a specific BAC.
Walk-and-Turn
Nine heel-to-toe steps along a line, a specific turn, nine steps back. Officers watch for eight clues: starting too soon, losing balance during instructions, stopping while walking, failing to touch heel to toe, stepping off the line, using arms for balance, making an improper turn, and taking the wrong number of steps.
One-Leg Stand
Raise one foot about six inches off the ground, keep the leg straight, look at the foot, and count aloud for about 30 seconds. Four clues: swaying, using arms for balance, hopping, and putting the foot down. Two or more clues suggest impairment under NHTSA research.2National Highway Traffic Safety Administration. DWI Detection and Standardized Field Sobriety Testing Participant Manual
Non-Standardized Tests
Some officers add exercises that never went through NHTSA validation: reciting the alphabet from a letter other than A, counting backward, finger-to-nose, or the Romberg balance test with head tilted back and eyes closed. These are also voluntary, and they carry less weight in court because they have no validated scoring system. A defense attorney can challenge them more easily than the three standardized tests.
How Results Get Challenged Later
If you take the tests and the case moves toward prosecution, the results are not the last word. Field sobriety tests break down in several predictable places.
Improper administration is the most common. The NHTSA validation studies assume officers follow the standardized procedures exactly. Skipped demonstrations, unclear instructions, or a rushed cadence can strip the results of the reliability that makes them admissible. Defense attorneys pull the officer’s SFST training records and compare the roadside performance to what the manual requires.
Medical conditions and physical limitations produce many of the same clues officers score as impairment. Inner ear disorders, neurological conditions, back and knee problems, and various medications affect balance and coordination. Nystagmus in particular can result from causes unrelated to alcohol, including brain injuries, inner ear inflammation, and some prescription drugs.
Environmental factors get less attention in police reports than they should. Uneven pavement, sloped shoulders, rain, wind, cold, flashing emergency lights, passing traffic, and footwear all affect performance. Dash camera and body camera footage often documents conditions the written report glossed over.
The stop itself can also be challenged. Every OWI case starts with the traffic stop, and the officer needs reasonable suspicion to make it. A stop based on an uncorroborated anonymous tip, a hunch, or a pretext that falls apart under scrutiny may lead to suppression of everything that followed, including the field sobriety results, the PBT, and the post-arrest chemical test.
Finally, the tests are subjective. Unlike a breath machine, they produce no number. What one officer scores as swaying, another might not. Cross-examination can expose confirmation bias where an officer who already suspects impairment interprets ambiguous performance as confirming it.
Making the Call at the Roadside
Michigan’s alcohol thresholds sit in the background of every OWI stop. The standard limit is 0.08 for drivers 21 and older; drivers under 21 face a 0.02 threshold; and the High BAC “super drunk” law triggers enhanced penalties at 0.17 or higher.3Michigan State Police. Impaired Driving Law An officer can arrest you at any BAC level if you show signs of impairment.
Knowing that field sobriety tests are voluntary is worth more than any script for how to handle a stop. Decline politely if you decline. Understand that the officer can still arrest you. Understand that the PBT and the post-arrest chemical test are different animals with different penalties, and that refusing the post-arrest chemical test costs you your license for at least a year regardless of the outcome of the criminal case. Ask for an attorney once you are under arrest. If a suspension notice arrives, calendar the 14-day hearing deadline the day you get it, because that deadline is one of the shortest in Michigan driving law and missing it forfeits the challenge.