Roadside stops, field sobriety tests and checkpoints in Michigan

Yes. A traffic stop is a seizure under the Fourth Amendment, so the officer needs a lawful basis: probable cause of a traffic violation, or at least an articulable and reasonable suspicion that the vehicle or someone in it is subject to seizure for a violation of law. A stop of a single car with no suspicion, only to check a license and registration, is not allowed. If the stop was not justified, a defense lawyer can ask the court to suppress what the officer found afterward.

Stopping a car is a seizure under the Fourth Amendment. In Delaware v Prouse, the United States Supreme Court held that, except where there is at least articulable and reasonable suspicion that a motorist is unlicensed, that the car is not registered, or that the vehicle or an occupant is otherwise subject to seizure for a violation of law, stopping a car and detaining the driver to check the license and registration is unreasonable (440 US 648, 663 (1979)). Michigan courts apply the same approach. An officer may briefly stop a person in a motor vehicle if the officer has a reasonable, articulable suspicion that the person is engaged in criminal activity (People v Steele, 292 Mich App 308, 314 (2011)), and a traffic stop must be justified at its start and reasonably related in scope to the reason for it (People v Williams, 472 Mich 308, 314 (2005)).

In an OWI case the reason is usually a traffic violation the officer saw or a report of erratic driving. The Court of Appeals has recognized that erratic driving can give rise to a reasonable suspicion of unlawful intoxication that justifies a stop (People v Christie, 206 Mich App 304, 309 (1994)), and that when a tip reports erratic driving, fewer facts are needed to justify an investigative stop (People v Barbarich, 291 Mich App 468, 481 (2011)). The reason for the stop and the reason for going further are separate questions. After a lawful stop, an officer may extend the detention long enough to resolve new suspicions that arise during it (Williams, 472 Mich at 315). The preliminary breath test statute adds its own threshold: the officer must have reasonable cause to believe the person was operating a vehicle and may have had his or her ability to operate affected by alcohol, a controlled substance, or another intoxicating substance (MCL 257.625a(2)).

Whether the stop was lawful is raised in the criminal case by a motion to suppress. Under People v Dillon, 296 Mich App 506, 509 (2012), whether evidence from a traffic stop must be suppressed turns on whether the officer had reasonable suspicion to justify the stop. A defense lawyer compares the reason the officer gives with the police report and any dash camera or body camera video.

Authority: Delaware v Prouse, 440 US 648, 663 (1979); People v Steele, 292 Mich App 308, 314 (2011); People v Williams, 472 Mich 308, 314-315 (2005); People v Christie, 206 Mich App 304, 309 (1994); People v Barbarich, 291 Mich App 468, 481 (2011); People v Dillon, 296 Mich App 506, 509 (2012); MCL 257.625a(2). Reviewed Oct. 2026.

Not as suspicionless sobriety checklanes. The United States Supreme Court held in 1990 that Michigan's checkpoint program did not violate the Fourth Amendment. In 1993 the Michigan Supreme Court held that sobriety checklanes violate article 1, section 11 of the Michigan Constitution, because the state's constitutional history does not support warrantless, suspicionless seizures of cars to enforce the criminal law. At any police stop, a driver must show a license on request, but is not obliged to answer questions.

The sobriety checkpoint question reached both courts in the same case. In Michigan Department of State Police v Sitz, the United States Supreme Court weighed the state's interest in preventing drunken driving, the extent to which a checkpoint system advances that interest, and the degree of intrusion on motorists who are briefly stopped, and concluded the balance favored the program under the Fourth Amendment (496 US 444, 455 (1990)). On remand, the Michigan Supreme Court decided the state constitutional question separately. It held that, because there is no support in the constitutional history of Michigan for the police to make warrantless and suspicionless seizures of automobiles to enforce the criminal law, sobriety checklanes violate art 1, section 11 of the Michigan Constitution (Sitz v Dep't of State Police, 443 Mich 744, 747 (1993)).

The Michigan decision was a facial challenge to the use of checkpoints generally, rather than a complaint about the treatment of a particular driver at a particular stop (443 Mich at 750). It does not prevent an officer from stopping an individual car for which the officer has a reasonable, articulable suspicion (People v Steele, 292 Mich App 308, 314 (2011)).

For a driver who is stopped, a few rules stay the same. A licensee must have the license in immediate possession while driving and display it on a police officer's demand (MCL 257.311). Beyond that, a detained motorist is not obliged to answer an officer's questions (Berkemer v McCarty, 468 US 420, 439 (1984)). Whether a particular stop was lawful, including one that began at a roadblock, is raised later in the criminal case by a motion to suppress.

Authority: Michigan Dep't of State Police v Sitz, 496 US 444, 455 (1990); Sitz v Dep't of State Police, 443 Mich 744, 747, 750 (1993); People v Steele, 292 Mich App 308, 314 (2011); Berkemer v McCarty, 468 US 420, 439 (1984); MCL 257.311. Reviewed Oct. 2026.

The three standardized tests are horizontal gaze nystagmus (an eye test), the walk and turn, and the one leg stand. The federal training manual reports that, in a San Diego study, correct arrest decisions were made 91% of the time using all three at the 0.08 level and above. The same manual says that result applies only when the tests are given in the prescribed and standardized manner. Michigan treats a test as standardized only if it was given in substantial compliance with those federal standards (MCL 257.62a).

The National Highway Traffic Safety Administration (NHTSA) trains officers on three tests: horizontal gaze nystagmus (HGN), the walk and turn (WAT), and the one leg stand (OLS). The manual describes laboratory research that found these three the most accurate of the tests studied, and later field studies. In the San Diego field study the manual describes, officers made correct arrest decisions 91% of the time based on the three tests at 0.08 BAC and above, and the individual tests were reported as 88% accurate for HGN, 79% for WAT and 83% for OLS (Session 8, pp 5, 10, 27, 45, 51). The manual also states that the validation applies only when the tests are administered in the prescribed and standardized manner, the standardized clues are used to assess performance, and the standardized criteria are used to interpret it, and that if any one element is changed, the validity may be compromised (Session 8, p 11).

Michigan law builds on that standard. A "standardized field sobriety test" is one of the standardized tests validated by NHTSA, and a test counts as standardized if it was administered in substantial compliance with NHTSA's standards (MCL 257.62a). A person qualified in giving these tests, including HGN, may testify once a foundation is shown, and a nonstandardized test is not barred if it complies with the Michigan Rules of Evidence (MCL 257.625s). The Court of Appeals has treated the foundation for HGN evidence as proper performance of the test by a qualified officer (People v Berger, 217 Mich App 213, 218 (1996)).

Two points follow for a Michigan case. First, the percentages above describe how well trained officers did in studies when the procedure was followed, so how the instructions were given, where the test was done and how the clues were scored are fair questions. Second, the tests are one piece of the evidence, alongside the driving, the officer's observations and any chemical test. The weight they carry is for the judge or jury.

Authority: NHTSA, DWI Detection and Standardized Field Sobriety Testing Participant Manual, Session 8, pp 5, 10-11, 27, 45, 51 (2/2023 curriculum, edited 4/2025); MCL 257.62a; MCL 257.625s; People v Berger, 217 Mich App 213, 218 (1996). Reviewed Oct. 2026.

They can still be offered, but these are the conditions the federal training materials themselves flag. NHTSA's manual says the walk and turn and one leg stand should be given on a reasonably dry, hard, level, non-slippery surface, that people over 65 or with back, leg or inner ear problems may have difficulty, and that people in heels over 2 inches should be given the chance to remove their shoes. Michigan treats a test as standardized only if it was given in substantial compliance with NHTSA's standards (MCL 257.62a).

The manual that trains officers on the standardized tests addresses these conditions directly. For the walk and turn, it says the test should be done, whenever possible, on a reasonably dry, hard, level, non-slippery surface. If the surface is not safe, the research it describes recommends asking the person to do the test elsewhere or giving only the HGN eye test. It adds that the original research suggested people over 65, or with back, leg or inner ear problems, had difficulty with the test, and that people in heels more than 2 inches high should be given the opportunity to remove their shoes (Session 8, p 39). The one leg stand carries the same surface guidance and the same recommendation, and the manual adds that people who are overweight by 50 or more pounds may have difficulty (Session 8, pp 46 to 47).

The manual also says that some conditions affect the eye test. It states that nystagmus may be caused by certain pathological disorders, such as brain damage or some diseases of the inner ear, and that when an eye movement looks abnormal to the officer, the person is not necessarily impaired (Session 8, p 18).

The same manual says the tests are valid when given in the standardized way (Session 8, p 11). Michigan law counts a test as a standardized field sobriety test only if it was administered in substantial compliance with NHTSA's standards (MCL 257.62a). An officer who qualifies may testify to the tests under MCL 257.625s, and a nonstandardized test is not barred if it meets the rules of evidence. In a case with an injury, a medical condition, footwear or poor footing, a defense lawyer asks what the officer knew about it, whether the person was offered a better surface or the chance to remove shoes, and whether the officer scored the clues the way the standards describe.

Authority: NHTSA, DWI Detection and Standardized Field Sobriety Testing Participant Manual, Session 8, pp 11, 18, 39, 46-47 (2/2023 curriculum, edited 4/2025); MCL 257.62a; MCL 257.625s. Reviewed Oct. 2026.

A driver is not required to answer. The United States Supreme Court has said a detained motorist is not obliged to respond to an officer's questions. It has also held that a person stopped in an ordinary traffic stop is not in custody for Miranda purposes, so the officer does not have to give warnings first, and what the driver says can be used later. Once a driver is arrested, custodial questioning requires warnings. A driver must still show a license on request, and refusing the roadside breath test is a civil infraction.

The Supreme Court addressed roadside questioning of drivers in Berkemer v McCarty. It said the detainee is not obliged to respond to an officer's questions (468 US 420, 439 (1984)). It also held that persons temporarily detained in ordinary traffic stops are not in custody for purposes of Miranda (468 US at 440), while a person subjected to custodial interrogation, such as after an arrest, is entitled to the Miranda safeguards regardless of the nature or severity of the offense, including a misdemeanor (468 US at 434).

The result for a roadside question like "Have you been drinking tonight?" is that the officer may ask it without warnings and the driver may decline to answer. The Michigan Court of Appeals applied the same reasoning in People v Steele, where an officer's brief questions during a stop were within the scope of the stop and did not amount to custodial interrogation (292 Mich App 308, 319 (2011)). An answer given at the roadside can therefore be written in the report and offered in the criminal case. The police report and any recorded statements of the defendant are among the items a defendant may request from the prosecutor (MCR 6.201(C)(2) and (3)).

Questions at the roadside are separate from two other things. A licensee must display the license on demand (MCL 257.311). And a peace officer with reasonable cause to believe the driver may be affected by alcohol or drugs may require a preliminary breath test, with a refusal being a civil infraction for most drivers (MCL 257.625a(2)(d)). After an arrest for OWI, the driver is considered to have consented to chemical tests of blood, breath or urine (MCL 257.625c(1)). Whether to answer any particular question is a decision a driver can talk through with a lawyer, ideally before giving a statement.

Authority: Berkemer v McCarty, 468 US 420, 434, 439, 440 (1984); People v Steele, 292 Mich App 308, 319 (2011); MCR 6.201(C)(2), (3); MCL 257.311; MCL 257.625a(2); MCL 257.625c(1). Reviewed Oct. 2026.

A traffic stop may last only as long as needed to handle the reason for it, plus whatever extra time is needed to resolve a new, reasonable suspicion that comes up during the stop. The United States Supreme Court has held that a stop cannot be prolonged beyond the time reasonably needed for its mission without reasonable suspicion of something more. The Michigan Supreme Court allows an officer to extend a stop long enough to resolve suspicion raised by new circumstances. The cases look at reasonableness on the facts, not a set number of minutes.

The starting point is that a traffic stop is a limited seizure. In Rodriguez v United States, the Supreme Court held that a stop justified only by a traffic violation becomes unlawful if it is prolonged beyond the time reasonably required to complete the mission of issuing a ticket, and that the stop may last no longer than needed to carry out that purpose (575 US 348; 135 S Ct 1609, 1614 (2015)). The case involved a dog sniff added after the officer finished the traffic tasks, and the Court held that adding unrelated checks without reasonable suspicion is not allowed.

Michigan applies a similar rule with room for new facts. A traffic stop is reasonable as long as the driver is held only to let the officer ask reasonable questions about the violation and its context for a reasonable period, and when a stop reveals a new set of circumstances, the officer may extend the detention long enough to resolve the suspicion raised (People v Williams, 472 Mich 308, 315 (2005)).

In a drunk driving investigation, the stop for a traffic violation may turn into an OWI investigation if the officer observes signs the officer can describe and articulate, such as the odor of alcohol, speech, or the way the driver acts. At that point the officer may ask the driver to do roadside exercises, and a peace officer with reasonable cause to believe the driver may be affected by alcohol or drugs may require a preliminary breath test (MCL 257.625a(2)). If the officer arrests the driver, the driver is considered to have consented to chemical tests (MCL 257.625c(1)). A defense lawyer looks at the time stamps on any video and the report to see when the traffic tasks were done and what the officer saw before the stop was extended.

Authority: Rodriguez v United States, 575 US 348; 135 S Ct 1609, 1614 (2015); People v Williams, 472 Mich 308, 315 (2005); MCL 257.625a(2); MCL 257.625c(1). Reviewed Oct. 2026.

Yes. Video is evidence like any other, and either side may offer it once it is authenticated. A recording lets the court or jury compare what the officer wrote or says with what was said and done: the instructions given, the surface, how the driver walked and spoke, and when each step happened. In a criminal case the defense can request the prosecution's tangible evidence, the police report and the defendant's recorded statements under MCR 6.201, and the prosecutor must respond within 21 days unless the court orders otherwise.

Recorded video can be offered at trial or at a motion hearing if it is authenticated, which requires evidence sufficient to support a finding that the item is what its proponent says it is, for example testimony from a witness with knowledge (MRE 901(a) and (b)(1)). An officer who recorded a stop can usually identify the recording. Once in evidence, it can be compared against the report and testimony on points that bear on the field tests: whether the officer gave the instructions the standards call for, what surface and lighting the person had, what the person was wearing, how the person moved and spoke, and the order and timing of events.

Discovery in a Michigan criminal case runs through MCR 6.201. On request, a party must provide a description of and an opportunity to inspect tangible physical evidence it may introduce at trial, including photographs and other items, with copies on request (MCR 6.201(A)(6)); the prosecutor must provide any exculpatory information or evidence known to the prosecutor (MCR 6.201(C)(1)), any police report and interrogation records (MCR 6.201(C)(2)), and any recorded statements by the defendant (MCR 6.201(C)(3)). The rule sets 21 days to comply with a request unless the court orders otherwise (MCR 6.201(G)), and if a party does not comply, the court may order disclosure, grant a continuance, bar the undisclosed material, or enter another appropriate order (MCR 6.201(K)).

Video helps or hurts depending on what it shows. It can confirm an officer's account as easily as it can contradict it, so what it shows is a factual matter for each case.

Authority: MRE 901(a), (b)(1); MCR 6.201(A)(6), (C)(1)-(3), (G), (K). Reviewed Oct. 2026.

A drug recognition evaluation is a 12-step protocol a specially trained officer uses to form an opinion about drug impairment. The steps include a breath test, an interview, eye and pulse checks, divided attention tests, pupil and muscle tone exams, and questioning. The implied consent statute lists blood, breath and urine tests (MCL 257.625c(1)) and does not mention this evaluation. In People v Bowden, a published decision, the Court of Appeals held that the officer's opinion testimony that a driver was impaired by marijuana was inadmissible under MRE 702 on that record.

A drug recognition evaluation (DRE) is a structured exam done by an officer who has special training. In People v Bowden, the testifying officer described the protocol as 12 steps: a preliminary breath test, an interview with the arresting officer, a preliminary examination and first pulse check, an eye examination, multiple divided attention tests, a vital signs and second pulse check, an examination of pupil sizes in various lighting conditions, an examination of muscle tone, a check for injection sites and third pulse check, an interrogation, the officer's formation of an opinion based on the facts gathered in the earlier steps, and a laboratory toxicology report (344 Mich App 171 (2022)).

Michigan's implied consent statute says a person who operates a vehicle is considered to have consented to chemical tests of blood, breath or urine when arrested for the listed offenses (MCL 257.625c(1)). It does not mention a drug recognition evaluation, and nothing in that section sets a penalty for declining one. What a driver says during the interview and interrogation steps is a separate question: an arrested person who is questioned in custody is entitled to Miranda warnings (Berkemer v McCarty, 468 US 420, 434 (1984)).

On admissibility, the Court of Appeals in Bowden held that the DRE officer's opinion that the driver was impaired by marijuana and unable to drive safely could not come in as scientific or technical opinion testimony under MRE 702, because the prosecution had not shown that the protocol had been validated as a reliable way to show a person's level of impairment from marijuana or its effect on driving ability. The court added that the ruling is not a blanket prohibition on the officer's testimony and that the prosecution could still offer the officer's testimony as a lay witness to the extent it is otherwise admissible. Bowden is a published decision about marijuana and a specific record, so its reach for other drugs or other records is a question for a lawyer to review.

Authority: People v Bowden, 344 Mich App 171 (2022); MCL 257.625c(1); Berkemer v McCarty, 468 US 420, 434 (1984). Reviewed Oct. 2026.

Yes, in some situations. Michigan's warrantless arrest statute lets an officer arrest for a misdemeanor punishable by more than 92 days when the officer has reasonable cause to believe the offense was committed and that the person committed it. A first-offense OWI carries up to 93 days. Other provisions cover a driver at a crash and a person found in the driver's seat of a vehicle stopped partly in the road. The prosecution must still prove the person operated the vehicle, which includes being in actual physical control of it.

MCL 764.15(1) lists when an officer may arrest without a warrant. Besides a misdemeanor committed in the officer's presence, it allows an arrest when the officer has reasonable cause to believe a misdemeanor punishable by imprisonment for more than 92 days has been committed and reasonable cause to believe the person committed it (MCL 764.15(1)(d)). A first-offense OWI is punishable by up to 93 days (MCL 257.625(9)(a)(ii)), so that provision can apply when no officer saw the driving. The statute also allows an arrest when the officer has reasonable cause to believe the person was the operator of a vehicle at the time of an accident and was operating it in violation of section 625 (MCL 764.15(1)(h)), and when the person is found in the driver's seat of a vehicle parked or stopped on a highway or street with any part of the vehicle in the roadway and the officer has reasonable cause to believe the person was operating in violation of section 625 (MCL 764.15(1)(i)). The Vehicle Code has matching language (MCL 257.625a(1)).

Whether the person was driving or operating is a separate element the prosecution must prove. The Vehicle Code defines operate as being in actual physical control of a vehicle (MCL 257.35a). In City of Plymouth v Longeway, the Court of Appeals held that a person clearly has actual physical control of a vehicle when starting the engine, applying the brakes, shifting from park to reverse and shifting back to park (296 Mich App 1, 3 (2012)). In those cases the questions are who was in the car, where it was and what shows how it got there. A defense lawyer looks at whether reasonable cause existed when the arrest was made and whether the evidence shows actual physical control.

Authority: MCL 764.15(1)(d), (h), (i); MCL 257.625(9)(a); MCL 257.35a; MCL 257.625a(1); City of Plymouth v Longeway, 296 Mich App 1, 3 (2012). Reviewed Oct. 2026.