Even if you are below the age of 21, you may be charged with DUI and suffer from the same consequences of a DUI 1st offense conviction including the mandatory jailtime and loss of license. However, under the underage DWI law, an individual between the ages of 16 and 21 may be convicted of DWI rather than DUI 1st offense.
Underage DWI does not carry any jailtime or probation time-period, but it has a mandatory one-year loss of license if convicted. However, unlike DUI 1st offense, an underage DWI is diversion-eligible meaning that the charge can be dismissed and expunged at the end of following any conditions negotiated with the prosecutor. Through a diversion, an underage DWI would not carry the mandatory loss of license which is extremely helpful because an underage DWI is not eligible for a restricted license.
Unlike a DUI first offense, whereas the legal limit is a BAC of .08%, an underage DWI only requires at BAC of .02% because of underage consumption being prohibited.