For most purposes, you become an adult when you turn 18, an age
established by The Age of Majority Act. However, other ages can be important depending on what legal issues are involved. For example, under Michigan law a person is considered an adult for purposes of the criminal law at age 17. So if a 17 year old is accused of a crime, he/she will be tried as an adult in either district or circuit court rather than in family court. Similarly, Michigan's Constitution establishes the legal drinking age as 21. Also, if you are emancipated, then you are legally an adult.
Emancipation is the legal process where a child between the ages of 16 and 18 becomes free from the control of his/her parents or legal guardian. How do I get emancipated by a court? Learn more about the process in the Michigan Courts Web site.