Drunk and drugged driving laws in Tennessee

By the end of this topic you can

• You can state the blood alcohol limits for adult drivers and for drivers under 21.
• You can explain implied consent and what refusing a test can lead to.
• You can describe the penalties for underage drinking and driving in Tennessee.
• You can explain why drugs, including prescription medicines, can lead to a DUI.

What you need to know and understand

• For drivers 21 and over, a blood alcohol concentration (BAC) of 0.08 or more is driving under the influence (DUI).
• For drivers aged 16 to 20, a BAC of 0.02 or more is underage driving while impaired.
• Underage driving while impaired brings a 1-year loss of license and a $250 fine, sometimes with public service.
• Drivers aged 18 to 20 convicted of buying, trying to buy or possessing alcohol lose their license for 1 year, even if no car was involved.
• Teens aged 13 to 17 caught possessing, using or selling alcohol or drugs lose driving privileges for 1 year or until age 17, whichever is longer.
• Driving under the influence of any intoxicant, including drugs, can be DUI even with no alcohol present.
• DUI, refusing a test and underage driving while impaired can each require SR-22 proof of insurance.

Zero tolerance for Tennessee drivers under 21

For anyone under 21, even one drink can put you over the 0.02 limit. A conviction for underage driving while impaired costs you your license for a year and brings a fine. The rules reach beyond the car, too: alcohol offenses by teens can take away driving privileges even if they have never been licensed.

The simple rule is the safest: if you are under 21, do not drink at all, and never get in a car with a driver who has been drinking.

Implied consent and testing

By driving on Tennessee roads, you are treated as having agreed to a test of your breath or blood if an officer has reason to believe you are impaired. Refusing does not get you out of trouble. A refusal can lead to loss of your license and is one of the offenses that can require SR-22 insurance. Repeat or serious DUI cases may also require an ignition interlock device, which stops the car from starting if it detects alcohol on your breath.

Drugs and medicines

• Illegal drugs, including marijuana, can impair your driving and lead to a DUI charge.
• Prescription and over-the-counter medicines can cause drowsiness or slow reactions; read the label and ask a pharmacist.
• Mixing alcohol with drugs or medicines multiplies the effects.
• Only time sobers you up. Coffee, cold showers and fresh air do not lower your BAC.

Common mistakes

• Believing one beer is safe for an under-21 driver. It can be enough to reach 0.02.
• Thinking a prescription drug cannot cause a DUI. Impairment from any substance counts.
• Refusing a test expecting it to help. Refusal brings its own penalties.
• Driving the morning after heavy drinking. Alcohol can still be in your system.

Test yourself: Drunk and drugged driving laws in Tennessee

Answer each question, then read the explanation. Questions come in a random order each time.

Go deeper

• How to Get a Driver’s License in Tennessee
• Moving to Tennessee
• Tennessee 50 Hour Driving Certificate