Generally, a person can be convicted of a DUI for driving with a blood alcohol concentration (BAC) of .08% or more or while actually impaired by drugs or alcohol. These standard DUI laws apply regardless of the driver’s age. However, all states also have underage DUI laws that apply only to drivers who are under the age of 21.
Underage DUI laws—often called “zero tolerance” laws—prohibit underage motorists from driving with even a small amount of alcohol in their system. Depending on the state, an underage driver can typically be convicted of a zero-tolerance DUI for having a BAC of .02% or more, .01% or more, or any measurable amount of alcohol.
The penalties for an underage DUI depend on state law and the circumstances of the case. However, penalties generally fall into one two categories: “administrative” penalties imposed by the Department of Motor Vehicles (DMV) and “criminal” penalties imposed by the court. In some states, an underage DUI offense carries only administrative consequences. In other states, administrative and criminal penalties can result from an underage DUI.
In most states, the DMV will suspend the license of underage motorists caught driving with an amount of alcohol in their body that exceeds the zero-tolerance limit. Suspension periods vary but normally range from 90 days to one year for a first offense. (Underage drivers who refuse a blood or breath test will likely face longer suspensions.)
Administrative suspensions are typically triggered by a report the arresting officer submits notifying the DMV of the zero-tolerance violation. So, an administrative suspension is possible even if the driver is never convicted of any crime in court. An underage driver who wishes to challenge an administrative suspension generally must contact the DMV and request a hearing.
In states that make underage DUI a crime, the penalties are often less severe than those for a standard DUI. A standard DUI is generally a misdemeanor. But an underage DUI is an infraction (which is less serious than a misdemeanor) in some states. Infractions typically carry fines but no possibility of jail time. And in states where an underage DUI is a misdemeanor, state law normally sets the minimum and maximum penalties (fines and jail) lower than for standard DUI offenses.
Also, a DUI conviction might affect a young person's educational and work opportunities.
Being under 21 years old doesn’t shield a motorist from standard DUI charges. If there’s evidence that an underage motorist was driving with a BAC of .08% or more or while “under the influence” as defined by state law, the prosecutor will have the option of charging a standard DUI. A standard DUI conviction typically carries the same penalties regardless of the driver’s age.
If you’ve been arrested for driving under the influence, it’s important to get legal help. A qualified DUI attorney can let you know what you’re up against and whether you have any viable defenses.