Getting arrested for a DUI can feel like your entire life is about to be turned upside down. For many people, one of the most confusing parts is the breath or blood test. Maybe you had a couple of drinks, waited a bit, and thought you were fine to drive. Then you were stopped, tested later, and told your blood alcohol concentration (BAC) was over the legal limit. What happened?
One possible explanation is what’s known as the "rising blood alcohol" defense. This legal strategy challenges the idea that your BAC at the time of testing accurately reflects your level of intoxication while you were driving. In certain situations, it can be a powerful defense in court.
What is the rising blood alcohol defense?
The rising BAC defense is a legal argument used in DUI cases. It says that your BAC was actually below the legal limit while you were behind the wheel, but it continued to rise after you stopped driving. By the time the police gave you a breath or blood test, your BAC had increased.
In South Carolina, DUI law is clear. It’s illegal to drive with a BAC of 0.08 percent or higher. However, your BAC must be over the limit while you’re driving, not necessarily at the time of the test. If there’s a delay between when you were pulled over and when you were tested, your BAC could rise during that gap.
How does alcohol absorption work in the body?
Alcohol doesn’t hit your bloodstream all at once. After you drink, alcohol is absorbed through your stomach and small intestine. This process can take anywhere from 30 minutes to 2 hours.
For example, let’s say you had two or three drinks quickly and then got in the car. You may have felt completely fine at that moment. But your body was still in the process of absorbing the alcohol. While you were driving, your BAC could have been under the legal limit. By the time you were tested at the police station, it might have climbed higher.
Here are a few things that influence how quickly your BAC rises:
- Whether you ate food while drinking.
- Your weight and metabolism.
- The type and amount of alcohol you consumed.
- Your drinking speed (slow sips vs. fast shots).
When does the rising BAC defense apply?
This defense doesn’t work in every DUI case. But there are some situations where it might make a real difference:
- There’s a long delay between being pulled over and being tested.
- Your BAC result is barely over the limit (like 0.08 or 0.09).
- You didn’t show clear signs of intoxication while driving.
- There’s evidence you had your last drink just before driving.
In those situations, your attorney can argue that your BAC was still on the rise and that you were not legally impaired at the time you were driving. For example, let’s say you finish your last drink at 9:30 p.m. and start driving home at 9:45. You’re pulled over at 10:00 for a broken tail light. The officer doesn’t see any major signs of intoxication but decides to take you in for testing. You get a breath test at 10:45 p.m., and it reads 0.09 percent.
What kind of evidence is needed?
To use the rising BAC defense, timing is everything. Your lawyer will need to build a timeline showing:
- When you had your last drink.
- When you started and stopped driving.
- When the breath or blood test happened.
- What you ate and drank before driving.
- Any witnesses or receipts that support your version of events.
Often, this defense also requires expert testimony. A toxicologist may be brought in to explain how alcohol is absorbed in the body and how your BAC could have changed over time. This scientific backing is important to show the court that the rising BAC theory applies in your case.
Are there challenges with this defense?
While the rising BAC defense can be compelling, it’s not always easy to prove. Prosecutors might argue that your BAC was already high when you were driving. Or they might point to your behavior at the scene (e.g., slurred speech or unsteady movement) as proof that you were impaired. Some judges also view this defense with skepticism unless there’s solid, scientific evidence to back it up. That’s why it’s important to work with a DUI lawyer who understands the law and knows how to build a persuasive case.
It’s also worth noting that in South Carolina, you can still be convicted of DUI even if your BAC is below 0.08 percent. If an officer or prosecutor believes you were impaired based on your behavior or driving pattern, they can pursue charges. The rising BAC defense doesn’t help much if there’s strong video evidence or testimony that you were clearly intoxicated.
Why is having an experienced DUI lawyer important?
Don’t assume a failed breath test means an automatic conviction. DUI charges are complicated, and there may be more options than you realize. If your BAC was close to the limit and there was a delay before your test, the rising BAC defense could help your case.
The rising BAC defense is one of several strategies a skilled DUI attorney might use, but it takes extensive knowledge and preparation. A South Carolina DUI defense lawyer needs to understand both the legal and scientific sides of your case.
Attorney Matt Bodman knows how to challenge DUI charges from every angle. As a former prosecutor, Matt understands how the state builds its case and how to dismantle it. He can review every detail, from the traffic stop to the timing of your BAC test, and determine whether a rising BAC defense is a viable path for your situation.
To protect your rights and your future, contact us online or call our Columbia law office today for a free, confidential consultation. We’ll walk you through your options and fight for the best possible outcome in your DUI case.
"Matt was such a blessing! He helped me through my case and was there for me step by step. He gave me his cell phone number and was there when I had a question or concern. I couldn't be happier with the result of my case, and I wouldn't think twice about calling him to represent me again!" - Google review, ⭐⭐⭐⭐⭐
