From Traffic Infraction to DUI Arrest: Part 3 Information Gathering

In Part 3 in our series, we will delve into the nature of the information that the officer is able to gather from you and how that has an impact in your DUI case. The most important thing to keep in mind is that you should not feel forced or compelled to say anything to the officer who interacts with you. Your only legal obligation is to provide license, registration, and proof of insurance in this scenario, not to provide any information which the officer will seek to use against you to support your arrest for Driving under the Influence in Ventura County. Similarly, you do not have to “consent” to perform the roadside exercises labeled by law enforcement as so-called “field sobriety tests” and you do not have to agree to provide a pre-arrest breath test sample, which is known as the preliminary alcohol screening (PAS) breath test.

From the officer’s point of view, it is very important that he collect drinking pattern information in order to be able to bring a case to the D.A.’s office that they can file and prove in court. It is not enough for an officer to simply have a breath test result in a case; he must also try to get from you information about what you had to drink, how many drinks you had, and the timeframe for drinking/ start and stop times in order to support the case against you. Full, complete, and accurate drinking pattern information is necessary in order to perform the calculation that is required to go back in time, so to speak, to prove a past blood alcohol level (your blood alcohol level at point of actual driving) based on a later test result. If the only known information is the time of driving, the time of the test, and the result of the test, you cannot reliably prove blood alcohol level at the time of driving without making an assumption as to where the driver is on the so-called blood alcohol curve. This important calculation is known as “retrograde extrapolation” and it is the heart of the D.A.’s case.

In order to attempt to prove blood alcohol level at time of driving, the D.A. will use its own forensic toxicologist from the law enforcement agency crime lab to testify. As your defense team, we have our own forensic toxicology specialist on your side, to help protect your rights in the system. In my own experiences cross-examining the prosecution’s forensic toxicologist, I can tell you that the prosecution “scientist” will admit under cross-examination that, where drinking pattern information is missing or unreliable, it is not possible to reliably do the retrograde extrapolation calculation, without making a big assumption as to where the client is on the so-called “blood alcohol curve.” Your own defense forensic toxicology specialist, as a scientist with over 30 years of experience in the Los Angeles Sheriff’s Dept crime lab. will explain how it is not scientifically appropriate to make such an assumption. Science relies on facts, not guessing games, conjecture, or assumptions. That is the level of proof that the case against you must be held to when we subject it to questioning and explore areas of reasonable doubt as your DUI defense team.

So what can you do, if you are stopped, in order to increase your fighting chances? If you are reading this in advance as kind of a cautionary tale, then what you can take away from this is “say nothing.” The more information that is provided, even something as seemingly innocuous as 007 saying one martini, shaken not stirred, after saving the world one hour prior to his stop for speeding, will be used against him… and similarly, any information you provide will be used against you. Often, however, people are reading this after the fact. What can we do to put you in the best possible position in your case then? There are several things we as your DUI defense team can do to help. First, we can explain, using the science to your benefit, that the information is deficient and that no scientifically reliable opinion can be reached. This is often the case when the officer fails to collect complete and detailed information, or when the client does not provide full information. The officer is trying to find out: the number of drinks, the kind of drinks, the quantity in terms of fluid ounces of drinks, and the timeframe for drinking. If any of that information is either deficient or not provided, that creates a scenario where any attempted calculation as to blood alcohol content at the time of driving could be inaccurate. In the case of two explanations for the same circumstantial evidence, one that points to innocence and one that points to guilt, the jury will be instructed that it is their duty to choose the explanation that points to innocence in order to preserve the presumption of innocence and guarantee our proof beyond a reasonable doubt standard.

So we have reviewed how inaccuracy creeps in in cases of assumptions and erodes the reliability of the science that is the basis for proving any DUI charge against you. What are the implications if we do not know when drinking started and when drinking stopped? In that case, we do not know where a driver is on the so-called blood alcohol curve, which is a trajectory of how his body metabolizes and absorbs alcohol. For example, if a person had been drinking shortly before driving, such as the scenario when a client is stopped very shortly after leaving a bar or restaurant, this may give rise to a defense known as “rising blood alcohol.” This means that, at the time of driving, your blood alcohol level is lower in your system and possibly even below the legal limit, but later, when you are tested via breath or blood in your final test, the alcohol has gone up in your system, reading above the legal limit. In that situation, the later blood alcohol reading is not an accurate reflection of the driver’s blood alcohol content at the time of actual driving. The crux of the charge is that a driver is, at the point of actual driving, driving with .08% or higher BAC. A later test result is only relevant as a measure of proof if it, in fact, reliably depicts blood alcohol level at point of driving.

At the Law Office of Jennifer Zide, we subject any test result to the ultimate scrutiny of questioning and review by your own defense forensic toxicology specialist, whose review is included in your case retainer at no additional charge. Our forensic toxicology specialist consults with me, as your defense attorney, so that I can distill his main points to empower you and keep you informed in the system. Your forensic toxicology specialist is also available for a conference with you, again at no additional charge, to review your scientific defenses and to answer any questions from you directly. Why? Because at the Law Office of Jennifer Zide, we believe in empowering you in the system, in providing a full review of your case, and in providing you with all the information you need to make the best decisions about your defenses and your options. If you have questions about the science in your case, we at the Law Office of Jennifer Zide are here to help. To discuss any questions about your DUI breath or blood test, or the inaccuracy of your DUI test result, please contact us today at or call us at (805) 669-9744. At the Law Office of Jennifer Zide, we are always on your side. Your freedom is our business.