Well, first of all, since I'm not sure if it's been said: don't hit people who insult you, and you won't find yourself in these situations. That being said, the outcome is going to be heavily dependent on the county you're in and the District Attorney's office you're dealing with:
-In some counties, the DA may not even find it worthwhile to charge, figuring that the school can take care of the matter; just because you commit a crime doesn't mean you have to be prosecuted. -Assuming you do get charged, if it's your first offense ever some counties -- Milwaukee County, for example -- have First Time Juvenile Offender Programs, where instead of being referred to a court for prosecution the juvenile probation agents make you do some programs, stay out of trouble, go to school, etc. If that works out, it ends there.
-If the FTJOP isn't available, the DA can still agree to a Consent Decree, which operates much like a Deferred Prosecution Agreement does in adult court: if you stay out of trouble and complete probation-like requirements for a period of time -- usually 12 months -- the State will dismiss the charge against you or modify it to an ordinance.
-If none of that works, you have the same options available to any defendant charged with a crime: plea to the charge or take it to trial. If you plea or are convicted at trial, the Court has the authority to order a fine, placement outside of your home in a shelter or in a juvenile detention facility like Lincoln Hills until your 18th birthday, or give you probation. Unless you have a long record or were otherwise on probation when this occurred, I doubt you'd get taken from your home, but that's going to depend on how serious the injuries were to the victim here.
No matter what, I'd strongly advise you to cooperate with the juvenile probation intake agents if they call you in to their office; avoiding them or ignoring them can only make your life worse. You may also want to look into hiring an attorney, though as a juvenile the Office of the Public Defender does tend to appoint you counsel if you can't afford a private one.
also in WI at 17, you are considered an adult so you would be in adult not juvenile court. Take this question off as it can be used as an admission.
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