I am routinely asked whether an OWI conviction is a felony, misdemeanor or crime.  The answer is it depends.  In determining if an OWI violation is criminal, the critical factor is the number of prior convictions.  If there is at least one prior countable conviction within the last 10 years or two prior countable convictions since 01/01/1989, then the new violation will be charged as a crime.  If there are no prior offenses, then the charge will be a civil violation. 

Assuming that there was no accident and no minors under 16 in the vehicle, an OWI 2nd, 3rd, or 4th would be classified as a misdemeanor offense.  If there was a minor in the vehicle, an OWI 3rd and 4th are classified as felony offenses, punishable by a possible prison sentence. 

An OWI 5th or subsequent offense is always classified as a felony in Wisconsin.  Causing injury by operating a motor vehicle while intoxicated is a misdemeanor (assuming no minors in the vehicle).  However, injury by intoxicated use of a motor vehicle and homicide by intoxicated use of a motor vehicle are classified as felonies.

The major difference between misdemeanors and felonies is the potential place of imprisonment.  For a felony, the court has the option to send you to prison.  In Wisconsin, the prison system is run by the Wisconsin Department of Corrections.  In a misdemeanor case, the court cannot send you to prison.  Any sentence would be served in county jail.  In Wisconsin, the jail is usually run by the local sheriff department.

In a civil OWI situation (OWI 1st) there is no jail sentence.