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About Blood Alcohol Concentration

What does blood alcohol concentration (BAC) have to do with drunk driving? A lot, but before we discuss California’s BAC laws, we’re going to take a look at BAC and what it means.

Blood or breath alcohol concentration is fairly self-explanatory. Without getting too scientific, BAC refers to the “amount” of alcohol that is in a person’s bloodstream or breath. Law enforcement uses breath, blood and urine tests to measure the BAC in a DUI suspect’s system.

Many people mistakenly believe that they can measure intoxication by a specific number of drinks, but number of drinks consumed is an unreliable measure because physiological factors, such as gender, body weight, and whether the person has eaten all affect how fast a body metabolizes alcohol.

Factors that affect BAC:

  • Sex
  • Food
  • Body weight
  • Type of alcoholic drink
  • Body fat percentage
  • How rapidly drinks are consumed

Remember, not all alcohol is equal. A 12 ounce beer is equivalent to a 4-5 ounce glass of wine, 7 ounces of malt liquor, or 1.25 ounces of 80 proof liquor.

The University of Notre Dame estimates that after four drinks, a 175 pound male would have a BAC of .100%, which is above the .08% legal limit. For a 150 pound male, it would only take three drinks to reach a BAC of .087%, also above the legal limit.

In contrast, it would take just two drinks for a 125 pound female to reach a BAC of .08%, and for a 150 pound female, it would take three drinks to reach a BAC of .101%, according to the University of Notre Dame.

Drinkers beware: you can’t drink coffee or Red Bull, or take a cold shower or jump in an icy lake to “sober up” and reduce your BAC. The ONLY thing that reduces BAC is time.

California’s ‘Per Se” Laws

In 1990, California enacted the immediate driver’s license suspension law, otherwise known as the “Administrative Per Se (APS)” license suspension law, making California the 28th state to enact such a law.

Under California’s APS law, it’s a crime to drive with a BAC of .08% or more. Under this law, the Department of Motor Vehicles (DMV) is required to suspend or revoke the driver’s license of any driver who has a BAC of .08% or higher, or who refuses to take a chemical test.

We hope this helps you better understand California’s BAC laws. If you’re facing DUI charges in Orange County, contact our office for a free case evaluation!