Underage drinking is not a criminal act in Wisconsin. It is called an "infraction". However, whether it is a misdemeanor or an infraction, it is still illegal for persons under the legal drinking age (21 years) to:
1.Purchase, procure, or attempt to procure, alcoholic beverages;
2.Possess or consume intoxicating liquor (including wine), except when accompanied by parent, guardian, or spouse who has attained legal drinking age;
3.Enter or be on a premises which has a license or permit to sell alcoholic beverages,
1.except if an underage person is an employee, resident, or boarder on the premises,
2.except if entering a Class A* License retail intoxicating liquor premises to purchase edibles,
3.except hotels, drug and grocery stores, bowling alleys, stadiums, restaurants, etc.
4.except Class B** License liquor premises if for an auction or marching and drilling, but not in the room where alcoholic beverages are sold or furnished.
5.except if the person is at least 18 and is contracted to entertain;
6.except on a premises when no alcoholic beverages are being sold or given away and the owner has notified law enforcement when underage persons will be allowed.
4.Obtain an I.D. card with inaccurate information;
5.Misrepresent his or her age for obtaining alcohol;
6.Carry false identification; or
7.Obtain an alcoholic beverage license or permit.
Underage drinking is a citation, not a crime. Your best bet is to go to court and see if you can get involved in the alcohol class that is offered in most municipalities. If you successfully complete the class, you may be able to get the ticket dismissed.
TJ is right. It's an ordinance violation. There is no real consequence to having this on your record but if there is an alcohol class you can participate in, it is wise to do so.