People v. Vangelder (2013)
___ Cal.4th ___ (Calif. Supreme Court – Docket No. S195423)
Expert testimony that properly working and approved breath-alcohol instruments do not sample breath samples as they are designed to, and thus do not produce reliable results, is irrelevant and inadmissible on the per se charge. The exclusion extends to physiological variability such as body and breath temperature, hematocrit level, gender, and breathing patterns.
The Court characterized expert witness Michael Hlastala’s proffered testimony as a “regulation-based argument” that improperly seeks to trump legislative determinations concerning alcohol limits in deep lung breath. It specifically declined to address whether the limitation applies to the impairment count (it would appear not to).
EDITOR’S NOTE: The holding does not seem to bar challenges based on mouth alcohol or GERD since these are contamination arguments that have nothing to do with partition ratio variability.
Have you been charged with a DUI San Francisco, DUI Marin, DUI Sonoma or DUI Napa? Paul Burglin is a Board Certified in DUI Defense San Francisco Bay area attorney who for over 25 years has specialized in drunk driving defense in San Francisco, Marin, Sonoma, Napa and surrounding communities. He is also the co-author of "California Drunk Driving Law"