Most states have a zero-tolerance (or near zero-tolerance) blood alcohol concentration (BAC) level of .02 for drivers under the legal drinking age (usually 21) that will result in a DUI/DWI charge. Some states set the BAC level at which a minor may be charged with DUI/DWI at .05. And some states will charge a minor driving a vehicle with a BAC of less than the state’s per se intoxication level (usually .08) with violating a zero-tolerance law such as driving while ability impaired (DWAI)—but will charge a minor with a BAC of .08 or more with per se (pronounced purr-say) DUI/DWI based on the state’s BAC-level definition of intoxication—or, in the absence of a chemical test of blood, breath, or urine, will charge the minor with common law DUI/DWI based on the police officer’s belief the minor was driving while intoxicated.

DUI/DWI criminal offenses, punishments, and terms used for underage DUI/DWI vary from state to state. These laws are generally located in a state’s statutes—often in the penal code or criminal code.

In South Carolina, the state enforces a zero-tolerance policy for underage drinking and driving. The legal drinking age is 21, and for drivers under this age, the state has set a Blood Alcohol Concentration (BAC) limit of .02 for DUI (Driving Under the Influence) charges. If an underage driver is found operating a vehicle with a BAC of .02 or higher, they can be charged with DUI. The state's per se intoxication level is .08, which applies to all drivers regardless of age. If an underage driver has a BAC of .08 or more, they will face the standard DUI charges applicable to adults. Additionally, South Carolina may impose penalties for driving with an ability impaired by alcohol (DWAI) for minors with a BAC lower than .08. The specific offenses, punishments, and terminology for underage DUI/DWI are detailed within South Carolina's statutes, which can be found in the state's penal or criminal code.