Rizio and Nelson California Law Blog

To be convicted of a DUI, a prosecutor has the burden of proving beyond a reasonable doubt that the defendant was driving under the influence of alcohol (and over the legal limit). The types of evidence which normally indicate acceptable evidence include: driving pattern, physical appearance, performance on field sobriety tests, and the results of chemical tests. Nevertheless, many people can drive well meeting or exceeding the legal limit (.08% BAC) with a perfect driving pattern, little or no physical intoxication symptoms, and pass the field sobriety tests as well as any sober person. This is primarily explained by the tolerance theory.

As the body adapts to alcohol use, it will learn to tolerate different levels of alcohol. The nervous system attempts to function normally in spite of the alcohol, which explains why it will quickly adapt itself to the level of alcohol in the body. In return, the intoxicating effect of the alcohol decreases. Nonetheless, prolonged consumption of large amounts of alcohol is not necessary in order for neural tolerance to develop.

In answer to this, the law adapted to convict people with a higher alcohol tolerance. In the early 1980s, California passed the first of its “per se” statutes. Per se is a Latin phrase meaning by itself, as such, or intrinsically. There is now a vehicle per se statute on record.

This law states: “It is unlawful for any person who has a .08 percent or more, by weight, of alcohol in his or her blood to drive a vehicle.” This section continues by stating: “It is a rebuttable presumption that the person had a .08 percent or more, by weight, of alcohol in his or her blood at the time of driving the vehicle if the person had a .08 percent or more, by weight, of alcohol in his or her blood at the time of the performance of a chemical test within three hours after driving.”

In a jury trial, the jury instructions, per CALJIC read:

“If the evidence establishes beyond a reasonable doubt that a chemical analysis of the defendant’s blood, breath, or urine established that there was 0.08 percent or more by weight of alcohol in the defendant’s blood at the time the test was performed, the trier of fact may, but need not, infer that the defendant was under the influence of an alcoholic beverage at the time of the alleged offense.”

The most frequently administered tests to determine blood alcohol content are breath and blood tests, but urine tests may be given where the other tests either are not available or where drugs are suspected.

If you or a loved one was arrested for DUI, please contact Rizio and Nelson’s skilled team of Driving Under the Influence/drunk driving lawyers immediately.