Los Angeles DUI prosecutions hinge on evidence such as blood or breath tests, so blood alcohol content (BAC) is critically important in a drunk driving case. When you're accused of drunk driving, your BAC will prove to be some of the most damning - or exonerating - evidence against you.

If your chemical test result that exceeded the legal limit - .08 percent BAC - there are many effective challenges to your blood or breath test. Los Angeles DUI lawyers from Lieber, Williams & Labin will aggressively challenge your chemical test result as part of a proven defense strategy to fight your drunk driving charge.

Even when your blood, breath or urine test is accurate, these test results only reveal your BAC at the time of testing, not at the time of driving. It's not against the law to be over the legal limit at the police station hours after your arrest, only when you were behind the wheel. Since a significant amount of time probably passed between the time you were pulled over and the time you were tested, this is a critical point in your Los Angeles DUI defense.

Every driver metabolizes alcohol differently because of gender, weight, metabolic rate, stomach contents, etc, so it's extremely difficult to look backward in time to pinpoint your BAC at an earlier time. Obviously, this difficulty will work to your advantage in defending your Los Angeles DUI charge.

When you drink alcohol, it goes first into your stomach before passing into your small intestine where most of the absorption takes place. The kind of alcohol you drink and your stomach contents before and during drinking impact the speed of alcohol absorption.

Alcohol begins to be eliminated immediately, but your body cannot eliminate alcohol as quickly as it absorbs it. This is what causes your BAC to rise. Alcohol absorption in the body can be compared to a bathtub with a slow drain - as water flows into the tub, it is draining at the same time, but because it flows in faster than it flows out, the level increases.

After you stop drinking, alcohol absorption continues. This causes your BAC to rise even after you stop drinking, until it reaches a peak or plateau. This peak level represents perfect equilibrium - your body is absorbing and eliminating alcohol at the same rate, so your BAC remains the same for roughly 15 to 45 minutes, depending on your stomach contents and metabolic rate.

Once your body completes the plateau stage, it enters the pure alcohol elimination phase. As long as you don't consume any more alcohol, your BAC will steadily decline at a rate of approximately .02 percent per hour. This rate of BAC decline is an average - like other aspects of metabolizing alcohol, it depends on many factors, including gender, body weight, etc.

When your body's alcohol elimination process is represented as a graph, it resembles a bell curve. Even if your blood or breath test showed that you were over the legal limit, a glance at the bell curve of alcohol absorption shows that you could have easily been under the legal limit while behind the wheel.

This is particularly likely if your breath test was performed while your body was still absorbing alcohol - the first half of the bell curve. An abundance of scientific research shows that breath tests performed during the absorptive phase overestimate true BAC by 40 to 100 percent.

The bottom line is that your alcohol absorption and elimination, and therefore your chemical test result in your Los Angeles DUI case, is greatly affected by your metabolic rates, eating patterns, fatigue levels, and many other factors. Police rarely conduct a thorough enough investigation to address these issues, but an experienced Los Angeles DUI attorney will thoroughly examine these issues and use them to your advantage in your California drunk driving case. To learn more about effective defenses to your drunk driving case, contact a skilled Los Angeles DUI attorney today for a free consultation.