Rising BAC

Rising BAC is a defense in some DUI cases. It argues that your blood alcohol concentration (BAC) was higher when you were tested by police than it was when you were actually driving.

Failing a breath test does not always mean you’re guilty of DUI. Breath tests and other chemical tests for DUI can be administered incorrectly by police, which can lead to false results. One of the most common errors police make is to wait too long to test you. If this may have happened in your case, you may be able to prove you are innocent using the “rising BAC” defense.

BAC stands for blood alcohol concentration and it refers to the amount of alcohol in your system at the time of the test. It’s illegal to have too high of a BAC while you’re driving, but tests aren’t given while driving—they’re given later, often an hour or more after you were first pulled over. Your BAC may have gone up in that time.

Why does BAC rise over time?

Most people assume that once you stop drinking, your BAC starts to go down. After all, shouldn’t it drop if you’re no longer putting alcohol in your system? Unfortunately, that’s not how BAC works. Understanding BAC can be the difference between going free and being wrongly convicted of DUI.

The reason BAC rises is because it takes time for your body to absorb alcohol. For example, if you drink a pint of beer, the alcohol from the beer doesn’t all enter your bloodstream at once. If it did, you would get suddenly drunk as soon as you set the beer down, and the “buzz” would wear off quickly as your body processed it. We all know that’s not how drinking works.

Instead, your stomach and intestines slowly absorb the alcohol from the beer over the course of an hour or longer. If you have food in your stomach, the process can be very slow. That means that when you first finish a beer, you might have the BAC of a sober person—but one or two hours later, long after you stopped drinking, you might “test” as if you’re drunk.

How long can police wait to test you?

If you had a couple of drinks, felt sober, and got in the car, your BAC may have been well within the legal limit. But if you got pulled over or were involved in an accident, and police test you an hour or two later, you could test as if you were over the limit—even if you weren’t when you were driving.

Unfortunately, there is no strict time limit for police to test you. Police are aware of rising BAC and they may try to avoid it by testing you as soon as possible. In other cases they may intentionally delay your test hoping to get a high test result. They know that most DUI defendants don’t hire lawyers and don’t know about rising BAC. This is a mistake. You can read more about how lawyers use the rising BAC defense here: What is a “rising BAC defense” in a DUI case?

The best way to find out whether the rising BAC defense could work for you is to speak to a DUI lawyer immediately. A good DUI lawyer will give you a free consultation and explain your legal options.

We can help. Let us connect you with an experienced Los Angeles DUI lawyer and get you a FREE consultation. Fill out the form to the right or call (310) 896-2724 and get your free consultation today.

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