What the prosecutor must prove in a Riverside DUI

In most Riverside DUI prosecutions there are two counts alleged:

  • Count I—Driving under the influence of alcohol and/or drugs (CVC §§23140, 23152(a) or 23153(a)); and
  • Count II—Driving with a blood-alcohol level of .08 percent (.05 if under 21) or higher (CVC §§23140, 23152(b) or 23153(b)).

Count I is the impairment count, sometimes referred to as the generic Riverside DUI charge. Count II is referred to as the per se charge. This latter charge is pretty straightforward—the individual is guilty of the offense if he is shown to have driven a motor vehicle with a .08 percent or higher blood alcohol level (“based upon grams of alcohol per 100 milliliters of blood or grams of alcohol per 210 liters of breath”). It does not matter if the individual has a high tolerance for alcohol and can operate a motor vehicle with the same caution and care as a sober driver—he is guilty of the (b) count if he was at or above the per se limit at the time of driving.

The impairment count (aka the (a) count) is more complex because an individual with just one drink in his system may be impaired, whereas another individual with 10 drinks in his system might not be. Prosecutors prove impairment circumstantially by introducing (a) a driving pattern that suggests impairment; (b) symptoms of the individual such as the odor of alcohol, red eyes, slurred speech, and unsteady gait; (c) poor performance on field sobriety tests; and/or (d) admissions of drinking and/or a feeling of impairment. Prosecutors will also often use a chemical test result to prove impairment, using their expert witness to opine that most people are impaired at an alcohol level of .05 percent or higher, and all people are impaired with an alcohol level of .08 percent or higher.

When it comes to drugs, there is no per se charge. Thus, the mere fact that an individual’s chemical test sample shows a high level of a drug or drugs does not make him guilty. The prosecutor must prove that the drug or drugs impaired him to such a degree that he no longer had the ability to drive with the caution and care of a sober person. Merely being under the influence of a drug—even one that is illegal—does not make one guilty of driving under the influence.

In the instructional 2009 case of People v. Torres, the defendant was detained after failing to completely stop until after a stop sign’s limit line—what the prosecution’s expert conceded was “a common traffic violation.” He presented objective symptoms of intoxication consistent with methamphetamine use, such as dilated pupils, facial twitching, stuttering speech, and profuse sweating. He appeared sleepy but his eyes were wide open, and he had a chemical odor. His urine sample showed the presence of meth and he admitted using meth. What seems to have hurt the prosecution was that its expert testified that to determine whether a person is under the influence of methamphetamine for driving purposes, “she would need to see field sobriety tests such as the Romberg exam, which assesses time perception, and any other tests that assess the person’s balance, coordination, ability to follow instructions, and ability to focus on multiple tasks at once.” She also acknowledged that “symptoms of fidgetiness, sweatiness, and a high pulse rate do not make a person an unsafe driver.”

The detaining officer was only permitted to testify about the symptoms of impairment from meth, but not about how it affected his ability to drive. Citing People v. Enriquez (1996) 42 Cal.App.4th 661, 665-666, the Court held “[i]t is not enough that the drug could impair an individual’s driving ability or that the person is under the influence to some detectible degree. Rather, the drug must actually impair the individual’s driving ability.” Given the absence of erratic driving, there was insufficient evidence to support a finding of guilt on the CVC §23152(a) charge.

Torres is a must read for those instances where the Riverside DUI prosecutor fails to present sufficient evidence tying impairment from alcohol and/or drugs to an inability to drive a motor vehicle with the caution and care of a sober person. A showing of mere impairment is not enough!

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