Tennessee DUI Laws (All You Need to Know)

Driving after a couple of drinks is a BIG NO-NO.

Not only do you put yourself in danger, but you also risk the lives of your passengers and others who share the road with you.

Moreover, you’re breaking Tennessee DUI laws and will face harsh penalties. 

But what exactly does the law say about DUI?

And what are the penalties you’ll face?

Why is DUI so dangerous?

We’re going to answer these questions and more. 

Here, you’ll know everything you need about Tennessee DUI laws. 

So let’s get right to it!

DUI Laws in Tennessee

There are several laws related to DUI in Tennessee. These include: 

• Illegal BAC Levels
• Under 21 Law
• Drugs and Driving
• Implied Consent
• No Refusal Law

Let’s look at the details.

Illegal BAC Levels

Blood alcohol concentration (BAC) refers to the amount of alcohol in your system. 

BAC is measured in percentage.

And in Tennessee, the illegal BAC levels are as follows:

• 0.08% for drivers above 21 years old
• 0.04% for drivers that hold a commercial license

A BAC level of 0.08% means you have 8 drops of alcohol for every 100 drops of blood. 

If you are caught with these illegal levels or higher, you will be charged with DUI.

However, that’s not to say your driving ability is only impaired when your BAC level hits 0.08%. 

According to the National Highway Traffic and Safety Administration, impairment begins even if your BAC level is at 0.02%.

So the bottom line is — NEVER drive whenever you drink (no matter how little).

Under 21 Law

If you think Tennessee’s DUI laws are strict, wait until you read about the laws that apply to drivers under 21 years old. 

• Under 21 Illegal BAC Level: While the BAC threshold for most drivers is 0.08%, it’s only 0.02% for those under 21. This is because under-21-year-olds are not even allowed to drink alcohol yet, much less drive while under the influence. 

• 18 to 20 Alcohol Violations: You can lose your driving privileges for a year if you receive a conviction for purchasing (or attempting to purchase) or possessing alcoholic beverages. It applies whether or not you’re driving.

• Juvenile Offenders: Teens between 13 and 17 cannot consume, possess, or sell alcohol or drugs. A conviction means losing your driving privileges for a year (or until you turn 17, whichever comes first). The penalty applies even if you’ve never had a Tennessee-issued driver’s license.

Drugs and Driving

Remember, DUI stands for Driving Under the Influence — and the substance influencing you isn’t limited to alcohol.

You can have a BAC of 0% and still get a DUI charge if you have drugs in your system that are affecting your driving ability. 

Yes, these include substances like marijuana.

But it also covers everyday drugs, such as those you can buy over the counter.

Cold tablets, allergy remedies, and cough syrups may have side effects that result in impaired driving.

It also applies to medication your physician prescribes, such as tranquilizers or sedatives. So if your doctor needs you to take something, don’t forget to discuss its possible effects on driving.

Implied Consent

Tennessee’s Implied Consent Law states…

“When you begin driving in the state, you automatically agree to get tested for drug and alcohol content through breath, blood, or urine tests.”

So, if a police officer pulls you over because they have enough grounds to suspect you of DUI, you must undergo testing. 

Refusing to comply may cause you to lose your driving privileges for 12 months.

However, this is not a criminal offense — only a civil one that may come with some inconvenient penalties. 

No Refusal Law

In 2012, Tennessee passed the No Refusal Law.

This law allows law enforcement officers to get search warrants, allowing them to obtain blood samples for possible DUI charges.

Although it may put drivers in a bind, the law aims to help prevent crashes resulting in injuries or fatalities due to impaired driving.

DUI Penalties in Tennessee

The consequences of having a DUI in Tennessee are no joke — and these get progressively worse if you are a repeat offender.

Here’s a table that summarizes the DUI penalties in Tennessee:

Offense	Fine	License Suspension	Jail Time	Vehicle Seizure
First	$350 to $1,500	1 year	48 hours(7 days for a BAC of 0.20% or higher)	N/A
Second	$600 to $3,500	2 years	45 days to 11 months and 29 days	Subject to seizure and forfeiture
Third	$1,100 to $10,000	3 to 10 years	120 days to 11 months and 29 days	Subject to seizure and forfeiture
Fourth and Subsequent	$3,000 to $15,000	At least 5 years	150 days to the maximum allowable length for a Class E felony	Subject to seizure and forfeiture

Of course, you can expect bigger fines, longer license suspension, and extended jail time if you commit:

• Aggravated DUI – DUI results in a bodily injury
• Vehicular Homicide – DUI results in death
• Drunk Driving Child Protection Act – committed DUI with a child under 18 in the vehicle

Besides all these penalties, a judge may also require you to do the following:

• Undergo a drug and alcohol assessment and receive treatment if necessary
• Go to an alcohol safety DUI school program
• Attend a drug or alcohol rehabilitation program at a treatment facility (second offense onward)
• Financially compensate a person who suffered a personal injury or loss due to the DUI
• Install an Ignition Interlock Device (when you get your license back)

What Affects Blood Alcohol Concentration (BAC)

It’s easy to say that drinking X number of bottles makes your BAC level reach a specific point — but the process is more complicated than that. 

Here are the different factors that affect your BAC level:

• How much you drink: Logically, the more alcohol you have within a set period, the higher your BAC becomes.

• How fast you drink: The less time between alcoholic drinks, the sooner your BAC rises.

• How much you weigh: People with less body fat and a slighter build tend to get affected by alcohol sooner.

• Whether or not you ate: Drinking with a full stomach causes your body to absorb alcohol slower — however, it’ll still affect you after a while.

• General health: Your liver processes around 90% of the alcohol in your body, so a damaged organ means you’re more likely to retain alcohol longer (and your BAC remains high).

Effects of Alcohol on Driving

Another crucial thing to explore is what happens to your driving ability when you drink.

Driving requires you to do multiple things — watch the road, observe other vehicles, look out for hazards, and ensure you remain at a safe speed.

Alcohol, by nature, is a downer, which means it slows down your faculties. So all the things you must do while behind the wheel become more challenging.

There are four crucial facets that alcohol affects:

• Judgment: You’re more likely to take unnecessary risks when drunk, such as speeding, improper passing, or just plain showing off.

• Vision: Out of all your senses, vision is the one alcohol affects in multiple ways. Driving while intoxicated means having less clarity, poorer glare vision, and reduced glare recovery. It also impacts depth perception, so you may think there’s more space between you and the car in front of you than there really is.

• Coordination and Reaction Time: Remember, you use your hands and feet simultaneously when you drive, requiring coordination. You have less of that when you drink, similar to when you can’t walk straight. You also take more time to respond to your environment, which may lead to a crash.

• Concentration and Alertness: Alcohol slows down your system, so it takes longer to register other vehicles or hazards on the road. You may also have difficulty keeping your focus.

How to Prevent DUI

Drinking while intoxicated is a choice.

If you can choose to do it, you can also choose to do things that prevent it from happening. 

Consider the following:

• When attending a social gathering, make sure you have a designated driver.
• When leaving, ride with a friend who didn’t drink.
• Give your keys to someone who won’t drink and won’t let you drive if you do.
• Limit yourself to non-alcoholic drinks.
• Take a cab or a rideshare vehicle to get home.

These may seem like little things, but they can make a HUGE difference.

Frequently Asked Questions About DUI in Tennessee

How Likely is Jail Time for the First DUI in Tennessee?

You can spend 48 hours behind bars, even if it’s your first DUI offense.

Is DUI a Felony in Tennessee?

Typically, a DUI conviction is a misdemeanor. However, on your fourth conviction, or if it results in injury, death, or breaks the Drunk Driving Child Protection Act, it becomes a felony (the felony Class will depend on your situation).

How Do I Get Out of a DUI in Tennessee?

Before you plead guilty to a DUI charge, see if either of these can work for you:

• Challenge the DUI stop. Remember, a police officer must have a legal basis for pulling you over. If he didn’t, you might get out of your DUI charge.

• Challenge the results of the blood or breath test. The arresting officer must give proper instructions about taking the field sobriety test. Failing to do so or inaccurately interpreting the results may make the test inadmissible in court.

What is the Difference Between DUI and DWI in Tennessee?

Law enforcement officers charge drivers over 21 with Driving Under the Influence (DUI). If you’re under 21, it becomes Driving While Intoxicated (DWI).

Does a DUI Ever Go Away in Tennessee?

A DUI remains on your record for your lifetime. That’s another reason why you shouldn’t drink and drive.

The Wrap Up

And that is everything you need to know about Tennessee DUI laws. 

Knowing all this will encourage you to avoid drinking and driving. 

Remember, it’s never worth the consequences — whether injury, death, or the harsh penalties. 

And, although it’s technically not illegal to drive if your BAC is under 0.08%, you can still get a DUI charge if your driving’s impaired.

And it’s not always about alcohol — drugs (even prescribed ones) can put you in the hot seat if you get behind the wheel.

In the end, it’s always better to play it safe. 

If you’re not in the condition to drive, DON’T.