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Examining the Arresting Officer in a California DUI case

Typically, the first witness for the prosecution in a California drunk-driving case is the arresting officer.  While the officer’s testimony can undoubtedly have a strong impact on the defense’s case, it does not mean that all is lost.  The arresting officer usually begins by testifying to the driving pattern of the California DUI suspect prior to the stop.  This is where the officer attempts to establish “probable cause” for the stop.  The officer may state that the  CA DUI defendant was weaving between lanes, perhaps only briefly encroaching into the neighboring lane, or that the DUI defendant was driving without headlights.  It is important to note that California courts have ruled that such occurrences do not always justify “probable cause” for a DUI traffic stop.  For instance, if it can be established that the DUI defendant was on his or her cell phone, resulting in the weaving, then the court may actually rule that the officer did not have probable cause for the stop and, therefore, the case ends in a dismissal. 


The next thing that an arresting officer will generally testify to is how the California DUI defendant acted during the stop.  The officer may state that the defendant fumbled for his or her wallet, had trouble locating registration or driver’s license, and/or that the defendant stumbled and almost fell down when asked to get out of the car.  While these things may first appear bad for the defense and indicate intoxication, a skilled California DUI attorney will know how to show that even a sober person may do the same things.  Oftentimes, when testifying to why the arresting officer believed that defendants were intoxicated, the officer will state that he or she “smelled a strong odor of alcohol.”  An experienced California DUI Defense lawyer can often make such testimony appear foolish during cross-examination by getting the officer to admit that alcohol (ethanol) itself has no odor.  The fact is that “alcohol odor” actually stems from the mixing agent.

If a DUI defendant submitted to field sobriety testing, the officer’s training and experience in administering such tests will be discussed.  This is a critical subject in testimony and one that the California DUI defense attorney should carefully examine.  If it can be determined that the officer who administered the tests was not properly trained, then such testimony may be excluded at trial.  Following any such testimony, the officer will generally testify to any results from breath or chemical tests that were performed.  The officer will be asked either by the prosecution or during cross-examination to explain the procedures regarding chemical testing.  The  California Code of Regulations Title 17 outlines specific procedures that must be adhered to when administering DUI breath or blood alcohol-content tests.  Again, California DUI lawyers should carefully examine whether or not these procedures were followed.  Failure to follow these procedures can sometimes lead to a skilled California DUI attorney’s getting such evidence suppressed.

The Defense Approach to Officer Testimony

While sometimes it may first appear that a California DUI/DWI defense attorney is faced with damning testimony, there are strategic avenues that can be pursued to turn things around.  First of all, jurors can often relate to the fact that when pulled over by the police the person is nervous and maybe even emotional.  Because of this fact, an experienced California DUI attorney will ask the officer if it is possible that the CA DUI defendant simply may have been nervous and therefore fumbled around when asked to produce a driver’s license, registration, etc.  Furthermore, if the officer testified that the DUI defendant stumbled when getting out of the car, the California DUI lawyer may be able to get the officer to admit that the road was uneven, there was a slope in the road, it was raining and slippery, or that the defendant was stepping on a gravel surface, any of which might have caused the stumbling to occur.  Remember that it is the prosecution’s job to establish all facts of a case beyond a reasonable doubt.  If doubt can be raised as to why a DUI defendant stumbled, acted foolishly, or fumbled around for identification, registration, etc., then the California DUI defense Attorney has a plausible defense. 


Prosecutors in DUI cases often like to suggest that because the officer was experienced and trained, he or she has a “special ability” to distinguish when a driver is actually “under the influence” of alcohol or drugs and therefore, given such expertise, the jurors should believe the officer’s “opinion” that the California DUI defendant was, in fact, impaired.  However, a controlled study conducted by Rutgers University’s Alcohol Behavior Research Laboratory , has noted otherwise.  In this study, it was found that the police officer’s ability to determine the level of intoxication of a driver was no more accurate than that of, say, a bartender.  Furthermore, it was found that both police officers and bartenders were able to judge correctly a person’s level of intoxication by no more than only 25% of the time.  The bottom line here is that the skilled California DUI/DWI attorney has numerous defense strategies that he or she can use to rebut any testimony given by the police. 

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