How the “Rising BAC” Defense Works in a Prince William County DUI Case

When you drink, your blood alcohol concentration (BAC) does not rise to its maximum level immediately. Instead, it climbs gradually, and it can continue to climb for up to two hours (or longer) after you stop drinking. This can give rise to the “rising BAC” defense in some DUI cases.  

When the police arrest you for driving under the influence (DUI) in Virginia, it is up to prosecutors to prove that you were under the influence at the time of your arrest. If prosecutors cannot prove that you were under the influence while you were driving, you are entitled to have your DUI charge dismissed. Once you hire an experienced Prince William County DUI attorney to represent you, your attorney will be able to evaluate all potential options for preventing prosecutors from meeting their burden of proof.

One potential option is to assert the “rising BAC” defense in court.

This defense relies on the fact that your blood alcohol concentration (BAC) does not immediately rise to its maximum level when you stop drinking. While asserting this defense can be challenging, it may be a defense worth considering if your recorded BAC was close to the legal limit (or close to 0.15 percent or 0.20 percent, which are Virginia’s thresholds for enhanced penalties).   

How Does the “Rising BAC” Defense Work?

Let’s say the police pulled you over after a night out drinking. You decided to drive home shortly after your last drink. The officer who stopped you suspects that you were driving under the influence, and the officer asks you to take a breath or blood test in compliance with Virginia’s “implied consent” law.

By the time you provide a breath or blood sample, it could be anywhere from several minutes to a couple of hours after you stopped driving. As a result, in the period between your traffic stop and the time you provide a breath or blood sample, your BAC could rise—and it could rise significantly. If your BAC reading is not indicative of your BAC at the time of your arrest, prosecutors should not be able to use it against you.

This is the “rising BAC” defense.

In general, the longer it takes to test your breath or blood after your traffic stop, the less reliable your BAC reading will be. With that said, if your recorded BAC is extremely high, prosecutors may assert that your BAC necessarily must have been over the legal limit when you got pulled over (though it may be possible to argue that prosecutors can’t prove your BAC was over the 0.15 percent or 0.20 percent threshold). In all cases, an informed approach is required, and it is important to consult with an experienced Prince William County DUI attorney to determine whether asserting the “rising BAC” defense is a viable option under the circumstances.

What if Prosecutors Have Other Evidence that You Were Driving “Under the Influence?”

Another important factor to keep in mind is that relying on your BAC is not the only way prosecutors can secure a DUI conviction in Virginia. Under Virginia’s DUI statute, prosecutors can secure a conviction based on your BAC or other evidence that proves you were driving “under the influence” at the time of your arrest.

Even if prosecutors do not have a reliable BAC reading, they may still be able to use other evidence to prove that you were “under the influence.” This could include evidence such as:

• The arresting officer’s dash cam or body-worn camera footage
• The arresting officer’s testimony
• Testimony from eyewitnesses
• Your performance on the field sobriety tests (FSTs)
• Any statements you made during or after your arrest

These are just examples. As a result, even if you think you may be able to assert the “rising BAC” defense in your case, it will still be important to determine what other evidence prosecutors have in their possession.

FAQs: Asserting the “Rising BAC” Defense in Your Virginia DUI Case

How do I assert the “rising BAC” defense in a Virginia DUI case?

Asserting the “rising BAC” defense in a Virginia DUI case is complicated. It requires several forms of evidence, and you must be able to clearly explain to the court why your BAC reading is not indicative of your level of intoxication when you were driving. As a result, if you think you may have grounds to assert this defense, it will be important to have an experienced DUI attorney on your side.

What if it had already been an hour or two since my last drink?

If it had already been an hour or two since your last drink when you got pulled over, this could make it more difficult to assert the “rising BAC” defense successfully. An experienced DUI attorney will be able to assess your options and help you make an informed decision about how best to proceed.

Do I need a DUI attorney to assert the “rising BAC” defense in court?

While not legally required, hiring an attorney to help you assert the “rising BAC” defense is important for all of the reasons we discussed above. Also, keep in mind that even if you assert this defense successfully, prosecutors may still have other evidence they can use to secure a conviction.

How an Experienced DUI Attorney at Our Law Firm Can Help

If you are facing a DUI charge in Prince William County, our attorneys can thoroughly examine the facts of your case to determine what defenses you have available. We can then assert all viable defenses on your behalf and help you pursue a favorable plea bargain if warranted. Time is of the essence, so we strongly encourage you to contact us promptly.

Speak with a Prince William County DUI Attorney in Confidence Today

To speak with an experienced Prince William County DUI attorney about asserting the “rising BAC” defense, contact us today. Call 703-897-1777 or tell us how we can reach you online to arrange a free initial consultation.