Driving Under the Influence of Drugs in Michigan

Michigan has two kinds of drugged-driving offense. The first is impairment: OWI and OWVI both cover being affected by a controlled substance or another intoxicating substance, alone or combined with alcohol.^[1][2] The second is a "zero tolerance" rule in MCL 257.625(8): driving with any amount of a Schedule 1 controlled substance or cocaine in the body is a crime even if the driver is not impaired.^[3]

The impairment offenses: OWI and OWVI by drugs

MCL 257.625(1)(a) defines operating while intoxicated to include being "under the influence of alcoholic liquor, a controlled substance, or other intoxicating substance or a combination."^[1] OWVI under 625(3) covers the same substances when they visibly impair the ability to operate.^[2] The substances are defined this way:

• Controlled substance. The Vehicle Code adopts the Public Health Code's definition in MCL 333.7104, including controlled substance analogues.^[9]
• Intoxicating substance. A substance other than alcohol or a controlled substance that is either recognized as a drug in the U.S. Pharmacopoeia, Homeopathic Pharmacopoeia or National Formulary, or is a non-food substance, including vapors or fumes, used in a way or for a purpose it was not intended and that may cause intoxication.^[10]

The "other intoxicating substance" language took effect March 31, 2013; before then, the OWI provision covered only alcohol and controlled substances.^[11] The jury standard is the same as for alcohol: under the influence means the substance substantially lessened the ability to operate a vehicle in a normal manner, and the jury instruction applies that test to controlled and intoxicating substances as well as alcohol.^[12] See what "under the influence" means and prescription and over-the-counter drugs.

The any-amount offense: MCL 257.625(8)

Subsection (8) says a person may not operate a vehicle if the person has in his or her body "any amount of a controlled substance listed in schedule 1" of the Public Health Code, or of a substance described in MCL 333.7214(a)(iv).^[3] That second reference covers coca leaves and their derivatives, including cocaine.^[13] Impairment is not an element. The model jury instruction, M Crim JI 15.4, asks only whether, while operating, the defendant had "any amount" of the specific substance the prosecutor alleges in his or her body, along with the operating and place elements.^[14]

Marijuana is still on Michigan's Schedule 1, except marijuana handled in compliance with the act and as authorized by federal authority, which is Schedule 2.^[15] One limit applies to medical users: in People v Koon, the Michigan Supreme Court held that the Medical Marihuana Act supersedes 625(8) for a registered patient who has marijuana in his or her system but is not otherwise under the influence, unless the patient loses immunity by not acting in accordance with that act.^[16] How the marijuana laws interact with the driving offenses is covered in marijuana and driving.

Metabolites: the drug must actually be in the body

A metabolite is a byproduct the body creates as it breaks a drug down.^[6] Two Michigan Supreme Court decisions limit what a metabolite proves under 625(8):

• People v Feezel (2010). 11-carboxy-THC, "a byproduct of metabolism created when the body breaks down the psychoactive ingredient of marijuana," is not a Schedule 1 controlled substance.^[6] The Court overruled the earlier Derror decision in part.^[6]
• People v Stock (2021). The Court rejected an interpretation of "controlled substance" that would include any metabolite of cocaine, and reversed OWI-causing-death and serious-impairment convictions where the prosecution showed only an unidentified cocaine metabolite in urine, without evidence that cocaine itself was in the body.^[7]

These cases concern what the any-amount offense requires. They do not prevent a prosecution on the impairment theory, which the chemical-test statute leaves open to "any other admissible evidence."^[17] See THC blood tests.

No numeric drug limit

For alcohol, 0.08 or more is itself an offense.^[18] The Vehicle Code sets no comparable numeric threshold for THC; marijuana cases are charged as under the influence, visibly impaired, or any amount of a Schedule 1 substance.^[8] Claims online about a fixed nanogram limit in Michigan are not supported by the statute.^[8]

How drug cases are investigated and proved

Because there is no number, drug cases rely on a mix of evidence, each with its own rules:

• Blood and urine tests. A test showing the presence of a controlled substance or other intoxicating substance is admissible and presumed to reflect the person's condition at the time of driving.^[19] See blood tests.
• Drug recognition experts. The statute defines a certified drug recognition expert as an officer trained to recognize impairment from a controlled substance rather than, or in addition to, alcohol.^[20] In People v Bowden (2022), the Court of Appeals reversed a ruling that would have let a DRE testify about the degree of a driver's marijuana impairment, because the prosecution showed no valid connection between the DRE protocol and that conclusion.^[21] See drug recognition experts.
• Roadside oral-fluid tests. MCL 257.625t authorizes a one-calendar-year State Police pilot program, and only a certified DRE in a participating county may require the preliminary oral-fluid test.^[22][23] Refusing it is a civil infraction.^[24] The State Police's own report says a roadside result, positive or negative, does not determine whether a driver is impaired.^[25] See roadside saliva tests.
• Officer observations and field sobriety tests. Qualified witnesses may testify about standardized field sobriety tests on a proper foundation.^[26]

The guide to evidence in drugged-driving cases goes deeper.

The special finding in drug cases

When an OWI or OWVI charge rests on a controlled or intoxicating substance, the jury must make a specific written finding, or the judge must on a plea or bench trial, on whether the person was under the influence of or impaired by a drug.^[27] A drug finding is reported to the Secretary of State, and a record of the penalties is forwarded to the State Police, which keeps it as a public record for at least 7 years.^[28]

Penalties and license consequences

Offense	First-offense criminal penalty	License	Points
OWI by drugs, 625(1)(a)	Up to 93 days, $100 to $500, up to 360 hours of community service.[29]	180 days, no restricted license for 30 days.[4]	6[5]
Any amount of Schedule 1 or cocaine, 625(8)	Same as OWI.[3][29]	180 days, no restricted license for 30 days.[4]	6[5]
OWVI by drugs, 625(3)	Up to 93 days, up to $300, up to 360 hours.[30]	180 days, restricted license possible.[31]	4[32]

Repeat-offense rules are the same as for alcohol cases: a violation of 625(1) or (8) within 7 years of a prior conviction brings a mandatory fine and jail or community service, and after 2 or more priors at any time it is a felony.^[33][34] A 625(8) violation that causes death or serious impairment is charged under 625(4) or (5); the jury must also find the defendant voluntarily decided to drive knowing he or she had consumed or used a controlled substance.^[35][36][14] Full tables are in the penalties chart.

Common misunderstandings

• "If I wasn't high, I can't be charged." Not for Schedule 1 drugs and cocaine; 625(8) needs only any amount in the body, subject to the Koon rule for registered medical marijuana patients.^[3][16]
• "Any positive test means guilt." A metabolite that is not itself the listed substance does not prove the any-amount offense, under Feezel and Stock.^[6][7]
• "Michigan has a 5 nanogram THC limit." It does not; there is no numeric THC threshold in the Vehicle Code.^[8]
• "A roadside swab proves impairment." The State Police report says it does not determine impairment.^[25]