Winning a DUI case often requires looking far beyond the numbers on a breathalyzer printout. In a recent victory at the DMV Driver Safety Office, Hermosa Beach DUI Attorney Matthew Ruff successfully overturned a license suspension for a client despite two chemical test results showing a blood alcohol concentration (BAC) of .11%—well above the legal limit.
The Case: High Breath Test Results After a Traffic Incident
The case began in Hermosa Beach following a report of a minor traffic collision. When officers arrived and conducted a DUI investigation, the driver provided two breath samples, both returning a .11% BAC. Under California law, the DMV moves to automatically suspend the license of any driver with a BAC of .08% or higher at the time of driving.
The Strategy: The Science of the “Absorptive Phase”
Many drivers assume that a breath test result is final. However, Matthew Ruff knows that what matters most is the BAC at the precise time of driving, not the time of the test.
In this case, the defense centered on the “Rising Blood Alcohol Defense” theory. When a person consumes alcohol, it takes time for the body to fully absorb it into the bloodstream. During this “absorptive phase,” a person’s BAC level continues to climb. If a driver is stopped shortly after drinking, they may be below the legal limit while behind the wheel, even if they test over the limit thirty or sixty minutes later at the police station.
Expert Testimony Leads to a Total Set Aside
To prove this, Matthew brought in a forensic toxicologist to analyze the timelines of consumption, the timing of the driving, and the subsequent chemical tests. Using an innovative technique called retrograde extrapolation, the expert evidence demonstrated that because the client was still absorbing alcohol at the time of the stop, their BAC was actually below .08% while they were operating the vehicle.
By meticulously presenting this scientific data, Matthew Ruff convinced the DMV hearing officer that the police had failed to establish the client was over the legal limit at the time of the actual driving.
The Result: Full License Reinstatement
The DMV issued an Order of Set Aside and Reinstatement, meaning the DUI suspension was completely vacated. The client’s driving privileges were restored in full, and the “not guilty” finding at the administrative level provided a massive advantage for the defense.
This case serves as a critical reminder: breathalyzer results are not infallible. With the right legal strategy and scientific expertise, even a “high” BAC reading can be successfully challenged.
Using the defense of retrograde extrapolation and other techniques, Torrance DUI Attorney Matthew Ruff has been defending clients wrongly accused of drunk driving and winning DWI cases for over 30 years. If you are facing a DUI suspension in Torrance, Hermosa Beach, or the South Bay, contact Attorney Matthew Ruff today to protect your rights and your license.
