What is "Rising" Blood Alcohol and How Does it Affect DUI Offenses?

"How does my 10% BAC scientifically get UNDER the .08% legal limit?" First, the level of alcohol in drinker constantly changes. One's Blood Alcohol Concentration (BAC) in a Drunk Driving Case is the number reported AT THE TIME OF TESTING, but not AT THE TIME OF DRIVING. DMV suspends one's license if one's BAC is .08% or higher at the time of driving.

To suspend in California, DMV law requires it to affirmatively find - "Were you driving a motor vehicle when you had 0.08% or more by weight of alcohol in your blood?" In "rising" DUI defense attorney cases, the driver's true BAC at the time of driving is critical.

Alcohol consumed before driving would not have necessarily been absorbed in a body by time of driving. Booze must first absorb, before becoming part of the body. BAC increases. It then is absorbed at some time well after alcohol ingestion has stopped.

If the alcohol is absorbing before, during and/or after driving, the person's BAC level may actually increase or "rise" as time passes. Keep in mind a driver is tested usually after driving stopped.

If the BAC level still "rises" during driving, then the BAC at the time of the breath or blood test is more than one's BAC at the time of driving. So a driver in the "rising" process - with a reported .08% or higher BAC at the time of the test - actually had a lower BAC at the time of driving.

If over 21 year-old's BAC at the time of driving is .07% or less, DMV may not suspend. BAC's change over hours and minutes. 60 minutes in an hour and a DMV indicated .01% increase every 20 minutes or so. Less of a BAC at the time of driving considers drinking times - particularly the time of driver's last drink - in comparison to the time the person ceased driving.

Less of a BAC at the time of driving further considers the number of drinks the driver had, based on her or his weight. DMV's publishes technical charts which they mail whenever you renew your license or registration.

These publications state: "HOW TO USE THESE CHARTS: Find your weight chart. Then, look for the total number of drinks you have had and compare that to the time shown." Looking at the white, gray and black boxes (per the Legend portion of the charts) which depending on one's weight, a person can increase:

• .01%-.04% in one hour...
• .05%-.07% in the next hour...
• .08% or higher in next hour

Here's a couple of possible interpretations or set of examples for "rising" drivers at 189 pounds (or less) [applying DMV's publication]:

• .08% test taken 1 hour after a person's driving means BAC was .07%, .06% or .05% at the time of driving.
• .08% test taken 2 hours later means BAC was .04%, .03%, .02% or .01% at the time of driving.
• .11% test taken in 2nd hour means BAC was .07% at the time of driving.
• .11% test taken in 3d hour means BAC was .04% at the time of driving.

Is a driver's license suspended if BAC level is increasing at the time of driving. It depends on what the licensing agency decides: If evidence supports a finding the driver's alcohol level a) was not .08% or > at the time of driving, or b) was .07% or < at the time of driving, State gives driving privileges back.

A California DUI defense lawyer can help you assess your situation and prepare this defense if it applies. San Diego DUI Attorney Rick Mueller offers DUI information for San Diego county drunk driving arrests.

All content on Accidents.com is for informational purposes only and is NOT intended as legal or medical advice. Please seek advice from a professional on any related topics.

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