Kevin Kennedy spent three years trying impaired-driving cases for the State in Davidson County, so he knows exactly what a prosecutor looks for in a file involving a young driver: the reason for the stop, the driving pattern, roadside testing, camera footage, the chemical result, and the driver’s date of birth. Underage impaired-driving cases can carry consequences that reach well beyond the criminal courtroom because a conviction also affects driving privileges.
Tennessee has a separate underage driving while impaired statute for drivers under twenty-one. The law applies both to actual impairment and to an alcohol concentration of 0.02% or more, a much lower threshold than the adult per se DUI limit. For drivers eighteen to twenty, the offense is a Class A misdemeanor; for drivers under eighteen, the conduct is handled as a delinquent act in juvenile court.
What Is Underage Driving While Impaired in Tennessee?
Tenn. Code Ann. § 55-10-415 prohibits a person under twenty-one from driving or being in physical control of a motor-driven vehicle while under the influence of an intoxicant, marijuana, controlled substance, drug, substance affecting the central nervous system, or combination that impairs the ability to safely operate the vehicle.
The statute also creates an alcohol-concentration theory. A person under twenty-one may violate the law if the alcohol concentration in the person’s blood or breath is 0.02% or more, even if the State does not prove the degree of impairment required in a traditional adult DUI case.
Underage Driving While Impaired Versus DUI
Underage driving while impaired is separate from DUI under Tenn. Code Ann. § 55-10-401. Tennessee law expressly treats underage driving while impaired as a lesser included offense of DUI. That distinction can matter when the evidence does not support a full DUI conviction but does support the lower 0.02% underage threshold.
For a driver under twenty-one, prosecutors may charge DUI, underage driving while impaired, or both depending on the evidence and charging practice. The defense should examine the exact blood- or breath-alcohol result, the officer’s observations, driving behavior, and whether impairment can actually be proven.
The 0.02% Alcohol Threshold
The underage statute uses a 0.02% alcohol concentration threshold. That means even a relatively small amount of alcohol can potentially trigger the statute for a driver under twenty-one. The defense should nevertheless examine whether the chemical test was legally obtained and scientifically reliable.
Timing matters. A test may occur well after the driving, and the reported concentration does not automatically answer what the driver’s concentration was at the earlier time. Breath-machine maintenance, observation periods, blood-draw procedures, chain of custody, laboratory testing, and contamination issues can all be relevant.
Drivers Ages Eighteen Through Twenty
For a person who is at least eighteen but under twenty-one, underage driving while impaired is a Class A misdemeanor. The statute provides for a one-year driver-license suspension, a $250 fine, and public service work in the court’s discretion.
Because the statute sets specific penalties, the practical consequences can be substantial even when no crash occurred and the alcohol level was well below the adult 0.08% threshold.
Drivers Under Eighteen
For a person under eighteen, the same conduct is treated as a delinquent act rather than an adult criminal conviction. The statute provides for a one-year license suspension, a $250 fine, and public service work in the court’s discretion.
Juvenile procedure, confidentiality, disposition, and long-term consequences differ from adult criminal court. The defense should address both the impaired-driving allegation and the juvenile-court framework.
Common Defenses to Underage DUI or Underage Driving While Impaired
The strongest defense depends on whether the State relies on actual impairment, a 0.02% chemical-test result, or both. Traffic-stop legality, testing accuracy, actual physical control, and identification can all matter.
Challenge the Traffic Stop
Every roadside encounter begins with a legal question: did the officer have a valid reason to pull the car over? Curfew assumptions, a party call, or a hunch that teenagers had been drinking are not substitutes for reasonable suspicion. When recordings contradict the reported lane drift, speed, or equipment problem, the resulting evidence may be suppressed.
Challenge Chemical Testing
A 0.02% case rises or falls on the number, so the number deserves scrutiny. Was consent freely given by a teenager, or was a warrant required? Was the observation period honored, the vial handled correctly, the instrument certified, the lab protocol followed? At these low readings, small procedural errors can swallow the entire margin the State is relying on.
Challenge Impairment Evidence
Nervousness in front of police is ordinary for a young driver, and it looks a great deal like the clues officers are trained to count. Sleep loss, a sports injury, gravel shoulders, cold weather, or simply misheard instructions can all produce a failing score. An odor on someone’s breath establishes that a drink was consumed — nothing more. The footage frequently tells a calmer story than the arrest report.
How Kevin Kennedy Defends Underage DUI Cases
Kevin begins by reviewing why the vehicle was stopped, the driver’s age, the officer’s observations, field sobriety testing, statements, and any blood or breath evidence. He examines body-worn camera footage, dash-camera video, chemical-testing records, laboratory reports, witness statements, and the timeline between driving and testing.
His former-prosecutor experience helps him evaluate whether the State can prove the adult DUI standard, the underage 0.02% standard, or neither. Depending on the evidence, the defense may challenge the stop, actual physical control, impairment, chemical testing, or statements, seek dismissal or reduction, negotiate where appropriate, or prepare the case for trial. If your son, daughter, or you personally are dealing with an underage impaired-driving charge anywhere in Nashville or Middle Tennessee, call (615) 205-7311 and Kevin will walk through the case with you at no charge and in confidence.
Legal references: Tenn. Code Ann. §§ 55-10-401, 55-10-415, and 55-10-404. This page is general information, not legal advice.