The Difference Between DUI And OWI In Michigan

OWI is an acronym that stands for operating while intoxicated. This is the actual legal term used under Michigan law.

Under Michigan, operating while intoxicated (OWI) is defined as operating a vehicle:

• With a blood alcohol content (BAC) of .08% or greater
• With any amount of a controlled substance in the body
• While under the influence of any intoxicating liquor, or
• While under the influence of any controlled substance or intoxicating substance.

The Michigan state legislature in 1999 changed the acronyms for drunk driving to OWI from OUIL and UBAL to OWI.  Michigan legislatures under pressure from state prosecutors wanted to only use one term. The reason why state prosecutors wanted this change is so both legal theories could be used to get a conviction by a prosecutor.  Under current Michigan law, an OWI can be proved when the state is able to prove beyond a reasonable doubt, that a person was either operating under the influence of liquor (OUIL) or where operating a motor vehicle while having and unlawful bodily alcohol level (UBAL).

Under Michigan law in 1999, the legal limit was .10 blood alcohol context (BAC). Under the law during that time period, if a person was found to have a BAC higher than .07 but below .10 you were presumed to be impaired by alcohol. If a person’s BAC measured at .10 or higher, the presumption was a driver was intoxicated. Any driver who was found to be below a .07 was presumed to be neither impaired or intoxicated and thus not in violation of any statue under Michigan law relating to drunk driving.

However, the law in Michigan changed in 2003. The legal limit was suddenly dropped to .08. The presumption of not being under the influence was also removed from Michigan law.

Because of this, a person can now be convicted of drunk driving even if they blow a breath test below .07.

Under this theory, a prosecutor must prove that a person’s ability to drive a car or truck on any Michigan roadway was “substantially lessened” by the person’s use of alcohol.

Under the changed Michigan law, OWI can be proven when a person isn’t even using alcohol.  People are charged with OWI for being under the influence of Ambien or Xanax. The requirement of showing a person’s ability to drive has been “substantially lessened” by alcohol does stay the same.

Michigan has a lesser offense called “operating while visibly impaired” (OWVI). A person driver can be convicted of this lesser offense if they display signs of being impaired by alcohol.  A person who is materially impaired is considered “under the influence.”