Many North Carolina drivers know that 0.08% is the legal blood alcohol concentration limit for most adult drivers. That can create a common misconception: if a breath or blood test shows a BAC below 0.08%, you cannot be charged with driving while impaired.
North Carolina law is not that simple. A BAC of 0.08% or higher is one way the state can establish DWI, but it is not the only way. A driver with a BAC below 0.08% can still be arrested, charged, and potentially convicted if the state can prove the driver was impaired by alcohol, drugs, or another impairing substance.
What Is the Legal BAC Limit in North Carolina?
For most drivers, North Carolina's per se BAC limit is 0.08%. Under N.C. Gen. Stat. § 20-138.1, a person commits impaired driving if they drive on a highway, street, or public vehicular area after consuming enough alcohol to have an alcohol concentration of 0.08% or higher at a relevant time after driving.
However, North Carolina's DWI statute also separately prohibits driving while under the influence of an impairing substance. These are distinct ways for the prosecution to establish the same DWI offense.
This distinction matters. A BAC result below 0.08% does not automatically prove that a driver was sober or legally capable of driving.
Our North Carolina DWI defense attorneys can examine the BAC result along with the other evidence the state intends to use to establish impairment.
How Can You Get a DWI With a BAC Below 0.08%?
When the prosecution cannot rely on a BAC of 0.08% or higher, it may instead attempt to prove that an impairing substance appreciably affected the driver's physical or mental faculties.
North Carolina appellate courts have recognized that the state can establish DWI based on impairment even without proving a BAC of 0.08% or more.
Consider a driver who registers a 0.06% BAC. That number alone does not establish the 0.08% per se theory of DWI. However, suppose police also claim the driver:
- Was weaving between lanes
- Had difficulty standing or walking
- Had slurred speech
- Had red or glassy eyes
- Performed poorly on field sobriety tests
- Admitted consuming alcohol
- Exhibited other signs that officers associated with impairment
The state could attempt to use those observations to argue that the driver was appreciably impaired despite having a BAC below 0.08%.
Whether that evidence is actually sufficient is a separate question and can become an important issue in the defense.
What Does "Appreciably Impaired" Mean?
North Carolina courts have described being under the influence of an impairing substance as having one's physical or mental faculties, or both, appreciably impaired by the substance. The effect must be significant enough to be recognized and estimated.
This does not mean that consuming any amount of alcohol automatically establishes impairment.
Someone may legally consume alcohol and then drive as long as they are not impaired and do not otherwise violate North Carolina's alcohol concentration laws. The state's burden in a DWI case is to prove the elements of the offense, not simply that the defendant had consumed a drink.
That distinction can become especially important in a North Carolina DWI case involving a BAC below 0.08%.
What Evidence Can Police Use When Your BAC Is Under the Limit?
When a chemical test does not establish a BAC of 0.08% or higher, other evidence can take on greater importance.
Police and prosecutors may rely on observations and circumstances from before and during the traffic stop. Depending on the case, those could include:
- Driving behavior before the stop
- The reason the vehicle was stopped
- Odor of alcohol
- The driver's speech and coordination
- Statements about drinking or drug use
- Field sobriety test performance
- Officer observations
- Video from a patrol vehicle or body camera
- Witness testimony
- Evidence of a collision
North Carolina case law shows that courts look at the evidence of impairment rather than treating the mere consumption of alcohol as sufficient. In one appellate case, for example, the court found the circumstances insufficient to establish probable cause where the evidence included alcohol consumption and odor but lacked stronger indications of appreciable impairment.
The specific combination of evidence matters.
Does a Low BAC Help Your DWI Defense?
A BAC below 0.08% can be significant, but it should not be viewed as an automatic defense.
If prosecutors are pursuing a case based on alleged appreciable impairment, the defense may examine whether the officer's observations actually support that conclusion.
For example, there may be innocent explanations for certain observations commonly associated with impairment. Fatigue, allergies, anxiety, injuries, medical conditions, environmental conditions, and other circumstances could potentially affect someone's appearance or performance during a roadside investigation.
Video evidence can also be important. An officer's written report may describe a driver as unsteady or having difficulty following instructions. Body camera or dash camera footage may provide additional context about what actually occurred.
A North Carolina DWI defense should therefore consider the entire investigation rather than focusing exclusively on the BAC number.
What About Field Sobriety Tests?
Field sobriety tests are frequently used during North Carolina DWI investigations. Officers may use a driver's performance as part of their assessment of whether there is evidence of impairment.
However, field sobriety testing does not produce a BAC measurement. The results are based on observations of how the driver performs particular tasks.
When a BAC is below 0.08%, field sobriety test evidence may become particularly important to the prosecution's theory of the case.
The defense may examine issues such as how the tests were administered, whether instructions were properly given, the conditions where testing occurred, and whether physical or medical limitations could have affected performance.
Are the Rules Different for Commercial Drivers?
Yes. The alcohol concentration rules are different when someone is driving a commercial motor vehicle.
North Carolina law provides that a person can commit impaired driving in a commercial motor vehicle with an alcohol concentration of 0.04% or higher. The statute also separately prohibits driving a commercial vehicle while under the influence of an impairing substance.
As a result, a BAC that would be below the 0.08% per se threshold applicable to most adult drivers could still create serious legal consequences for someone operating a commercial motor vehicle.
Commercial drivers can also face significant professional and licensing consequences from an impaired-driving case.
What About Drivers Under 21?
North Carolina also has a separate alcohol-related driving law for people under 21.
The state's statutes include an offense for a person under 21 driving after consuming alcohol or drugs, meaning younger drivers should not assume that being below the standard 0.08% threshold protects them from charges.
North Carolina's license revocation laws likewise provide for consequences involving any alcohol concentration at a relevant time after driving when the driver is under 21 and the statutory requirements are satisfied.
These cases therefore need to be evaluated under the rules that apply specifically to underage drivers.
Can You Fight a North Carolina DWI Charge When Your BAC Was Under 0.08%?
Being under 0.08% does not automatically make a North Carolina DWI charge invalid. It can, however, change the issues that matter most in the case.
A defense attorney may examine:
- Whether the officer had a lawful basis for the traffic stop
- What evidence supposedly demonstrated impairment
- Whether field sobriety tests were administered appropriately
- Whether body camera footage supports the officer's account
- Whether there are alternative explanations for alleged signs of impairment
- Whether chemical testing procedures were properly followed
- Whether the prosecution can prove appreciable impairment beyond a reasonable doubt
North Carolina appellate decisions demonstrate that evidence of alcohol consumption is not necessarily the same thing as sufficient evidence of impairment. The strength of a DWI case depends on the totality of the evidence and the particular legal theory the state is pursuing.
Talk With a North Carolina DWI Defense Attorney
A BAC below 0.08% does not necessarily prevent a DWI charge in North Carolina. The state may still attempt to establish that alcohol, drugs, or another impairing substance appreciably affected your ability to drive. For commercial and underage drivers, different alcohol-related thresholds and rules may also apply.
If you are dealing with a DWI charge in North Carolina, our attorneys are here to help. Call us today or connect with us online to schedule a consultation.
