top ten tips: fighting a sonoma dui

The First 48 Hours After a DUI | Getting Your Driver's License Back | Easing the Consequences of a DUI | Fighting a Sonoma DUI

  1. Observed Driving
  2. Initial Police Detention
  3. Rising Blood Alcohol
  4. Drinking After Driving
  5. 15-Minute Observation & the Breath Machine
  6. Blood Tests
  7. The 3-Hour Presumption
  8. Chemical Test Refusals
  9. Necessity
  10. Police Reports

1. Observed Driving

Driving is a key element of the Sonoma County prosecutor's and Santa Rosa DMV's DUI case against you. If the government cannot prove that you were driving beyond a reasonable doubt in the criminal court case (or at Santa Rosa DMV the administrative law burden of proof is easier for the government, often called "by a preponderance" or "more likely than not" or "by 51%"), then your case may be a winner. You should discuss your specific matter with a Santa Rosa DUI attorney.

Someone Else Drove.

If someone else drove, not you, then this DUI defense is much stronger if you and the actual driver both stated at the time of initial contact with law enforcement that you were not the driver, and if the actual driver is still available to testify in your defense in a Sonoma County courtroom or at the Santa Rosa DMV. Note that this is not a new defense and the prosecutor will often fight hard against your Santa Rosa DUI lawyer because they know it is unlikely anyone else at the scene was tested for being over the DUI alcohol limit, so if they lose you then they lose the whole case.

Circumstantial Evidence of Driving.

Any good Sonoma County DUI attorney will tell you that even though it may be that no officer saw you driving, the Sonoma County District Attorney and the Santa Rosa DMV may introduce circumstantial evidence (as opposed to direct observation) of your driving, typically with facts such as you were found in the driver's seat, the vehicle is registered to you, the keys were in your pocket, the vehicle hood was warm to the touch, the seat was adjusted for your height, your own admission to driving, etc...

Although this was not always the law, it is true today that in California, circumstantial evidence of driving can support a DUI conviction and DMV suspension in the same way as direct evidence. Of course, if the police did not see you driving, but someone else did (for example, a roommate or relative, or someone who called 911 regarding "erratic driving"), then again, this type of evidence would support a DUI conviction and DMV suspension, although such witnesses would be subject to close scrutiny on cross examination if there is any doubt regarding the identity of a driver, or time of driving, as discussed below.

Substantial Time Lapse Between Driving And Stopped.

If you drove but had been parked or stopped for a long time (more than a couple hours) before law enforcement arrived, then your Sonoma County DUI lawyer should explain to you that additional issues may come into play. (See for example "3-hour Presumption" discussion in Tip #7, below, where both the Sonoma County District Attorney and the Santa Rosa DMV must establish a time of driving, and more fundamentally, was it reasonable at the time for Sonoma County law enforcement to believe at the time of arrest that you were DUI when driving hours before?).

2. Initial Police Detention

The best Sonoma DUI lawyers will be sure to ask you almost immediately one of the most important questions in connection with any DUI arrest, "how did you first come in contact with the police?"

If the initial encounter between you and the police was not consensual, meaning the officer didn't just walk up to you like anyone else, but rather you were pulled over first by patrol car lights, then a good Santa Rosa DUI attorney will explain to you that the police must have a warrant, or reasonable suspicion to believe a crime (a DUI or another crime) has been or is being committed, or some other compelling reason to stop or detain you and interfere with whatever you were doing before the encounter or interfering with your freedom to leave before the DUI arrest.

Typically, initial stops in Sonoma County DUI cases are justified by the officer asserting that he/she observed one or more vehicle code violations, such as speeding, failure to make a complete stop at stop sign or traffic signal, no front license plate, obscured rear license plate, no headlights at night, broken tail lights, dim license plate light, tinted windows, or peculiar driving behavior such as squealing tires, weaving, swerving, or other erratic driving. Click on the Resources page on this website for lists of Common Moving Violations and Equipment Violations which are often used to justify such initial detentions.

Both the Sonoma County DUI court case and the Santa Rosa DMV case will be dismissed if your Sonoma County DUI attorney can prove to the satisfaction of the judge and DMV hearing officer that the detaining police officer cannot justify the original stop or detention, even if the officer believed in good faith that there was a justifiable reason to stop you. This defense of an illegal stop under the Fourth Amendment arises if you were actually doing nothing wrong when you were stopped or detained and/or Sonoma County law enforcement had no reasonable cause to believe you had been driving under the influence. Any good Santa Rosa DUI lawyer will seriously consider filing a "Motion to Suppress Evidence" when DUI evidence was obtained as a result of an illegal police stop or encounter.

3. Rising Blood Alcohol

If your body is still absorbing alcohol at the time that the blood alcohol testing is administered to you by Sonoma County law enforcement, then the later test results in Santa Rosa will not be an accurate reflection of your alcohol level at the time of driving. This defense usually arises when you drank alcohol just prior to driving.

A Rising Blood Alcohol example.

Your Sonoma County DUI attorney should explain a rising blood alcohol case to you this way:

Let's say you live in Cloverdale and you arrive at a party in Petaluma at 10:00 p.m. You have had nothing to drink and you have no alcohol in your body. Minutes after arriving you drink three healthy shots of tequila on a dare. Right then you see your ex at the party and decide to go home. At 10:05 p.m. you leave and drive Highway 101 North from Petaluma to Cloverdale. As time progresses during your driving, your blood alcohol concentration ("BAC") will be rising. For example, when you reach Santa Rosa, your BAC may be .04%, still below the .08% legal limit. However, by the time you reach Healdsburg, your BAC may be at .11%, and by the time you reach home, your BAC may have reached close to twice the legal limit at .15%.

But what if you are stopped by Sonoma County CHP in Windsor? Let's say that your BAC at the time of that stop is .06%. But your alcohol absorption doesn't stop just because your vehicle stopped. By the time you take a breath test, typically 15-25 minutes after the police stopped you, your BAC may have risen to risen to .13%, approaching twice the legal limit. Click here to see Scientific Examples Of Rising Curves.

The defense.

The law allows the Sonoma County prosecutor a legal presumption, to argue to the jury in a Santa Rosa courtroom that the .13% result in the above example is presumed to be your BAC at the time of your driving (because obviously the police can never test you at the time you are actually driving). This presumption is discussed in further detail in Tip #7 of this section. But if your Santa Rosa DUI attorney can show by affirmative evidence that it is more likely your BAC was below .08% at the time you were observed driving (which is the only legally relevant time -- it is not illegal to be over .08 while stopped at the side of the road) then you may win your case in Sonoma County court and at Santa Rosa DMV.

This defense is strongest for a Sonoma DUI lawyer when your test results show lower blood alcohol levels and if you offered a credible drinking history, supporting an upward absorption graph, at the time you were interviewed by the Sonoma County police prior to arrest. If you took a preliminary breath test prior to arrest that actually shows you were below .08% with later tests showing modest gains, then you may have a very strong defense.

On the other hand, if you lied when interviewed at the scene (most people do), and said you had nothing to drink all night, or "just one drink hours ago," then your Sonoma County DUI lawyer may have difficulty convincing a Santa Rosa jury or the DMV later that you are telling the truth when you testify differently than the police report account by Sonoma County law enforcement. This is why Sonoma DUI lawyers nearly always suggest that during an encounter with law enforcement, it is best to say nothing at all about your activities, but never lie.

Click here to see an example of a winning DMV Case Applying the Rising BAC Defense.

4. Drinking After Driving

Your Sonoma DUI lawyer should explain that if you consumed alcohol subsequent to driving and prior to arrest, then the police officer's observations of your behavior later, and the alcohol test results later, cannot be an accurate reflection of your level of alcohol or impairment at the time of driving, which is actually the only legally relevant point in time; if you were drinking roadside, this may be a violation of the open container law, or perhaps even "drunk in public," or "attempted DUI," but if you weren't driving, or if you drank subsequent to driving, then these facts allow a Sonoma County DUI attorney to point to often fatal proof problems for the Sonoma County prosecutor and for the Santa Rosa DMV.

This defense is strongest for your Santa Rosa DUI lawyer when your test results show lower blood alcohol levels and/or if you offered a credible drinking history at the time you were interviewed by the Sonoma police before being arrested, and if there are disinterested witnesses (who don't know you) who can testify to the after-driving consumption, or if there is actual physical evidence to support the defense, such as 1/2 empty liquor bottles in the car, recent store receipts, etc. (see the Preserve Physical Evidence discussion in the Tips for the First 48 Hours articles on this site).

Sometimes the facts are present for such a defense, but at the time of arrest people think that they should deny they were drinking in the vehicle after stopping. This is a common error because people naturally don't want to admit to even further illegality when confronted by the police. But denying drinking after driving may very well destroy any chance your Sonoma County DUI lawyer might have had to present the defense and win your case in court or at the DMV hearing. See the related discussion of the 3-Hour Presumption in Tip #7.

5. 15-Minute Observation & the Breath Machine

Title 17

Sonoma County law enforcement testing of your alcohol levels must comply with state rules (called "Title 17") which legitimize a non-doctor (in other words, your arresting officer, lab technicians, etc) engaging medical procedures to determine the amount of alcohol in your body. Your Sonoma DUI attorney will explain to you that in order for test results to be valid in Sonoma County court or at the Santa Rosa DMV, certain procedural rules must be followed. You can see these rules by clicking here: Title 17 Rules (2018) or here for the earlier 2010 version. The burden is on the police and the government to show this fundamental compliance.

Mouth Alcohol and the 15-Minute Rule

In breath testing cases, one of these procedural rules is that you must be continuously observed by Sonoma County law enforcement for 15 minutes immediately prior to the test being taken to ensure that you did not belch, regurgitate, eat or drink, or otherwise have mouth alcohol or other foreign substances present which would cause the tests to produce falsely high results. Good Sonoma County DUI lawyers will examine the listed times for breath results in comparison to the time listed on the DUI arrest report for the officer's first observations of you. The best defense here is when the Sonoma officer arrives at an identified time prior to the DUI arrest and your Santa Rosa DUI lawyer can prove that the relevant breath tests are administered to you prior to the end of the 15-minute waiting period.

The Breath Machine

There are additional regulations in Title 17 which require that Sonoma County breath machines are approved devices, and calibrated at regular intervals and test within certain acceptable ranges of accuracy. Your Santa Rosa DUI attorney can subpoena and review calibration and maintenance records from the arresting agency in Sonoma County, and from the Santa Rosa lab of the Department of Justice, for possible defenses, particularly if your test results are relatively low.

Sonoma DUI lawyers see many Santa Rosa police agencies and Sonoma County law enforcement using a type of breath machine called the Alcotest 7410, which can be manipulated by the officer administering the test. See the California Attorney General's 7410 Information Bulletin. The YouTube video link provided below effectively demonstrates this vulnerability in the reliability of the machine, and therefore demonstrates a defense in the right circumstances, typically if there is additional evidence of sobriety, police foul play or other error during your DUI arrest. Click here to watch the demonstration (although this video effectively portrays the machine's defect, we do not endorse the demonstrator's general suggestion to refuse the breath test): Darryl Genis Demonstrates 7410 Vulnerability.


  1. 6. Blood Tests
  2. 7. The 3-Hour Presumption
  3. 8. Chemical Test Refusals
  4. 9. Necessity
  5. 10. Police Reports

6. Blood Tests

Blood Draw.

The California Vehicle Code requires that only certain licensed or qualified individuals in Santa Rosa may draw blood for testing, if acting at the request of a Sonoma County peace officer. These individuals are certified paramedics, or licensed as physicians and surgeons, registered nurses, vocational nurses, clinical laboratory scientists, clinical laboratory bioanalysis, or certified phlebotomy technicians, or unlicensed laboratory personnel employed by a licensed clinical laboratory and supervised and fully trained by one of the above. VC Section 23158, BPC Sections 1240-1246.5.

If the Sonoma County police report indicates that the individual who drew your blood for testing was not properly qualified under the law, then your Sonoma County DUI attorney can fight any effort to use the test results against you in Sonoma County Superior Court or at the Santa Rosa DMV. Sometimes the police report simply lists a name without any further indication of what job title or professional qualifications are associated with the individual who drew your blood following the DUI arrest.

Further investigation may be conducted to determine if a defense of noncompliance is applicable to your blood draw. This approach may be particularly effective if other factors indicate a possible error in blood sample collection, such as your recollection of how much you drank differing widely from an unexpectedly high blood test result, or preliminary breath testing results are inexplicably different from the blood test result, or your own recollection of poor sanitary conditions during the blood draw or bruising after multiple blood draw attempts, or other evidence that the person drawing your blood was unqualified or committed meaningful errors.

Retesting Your Blood Sample.

Government testing mistakes do happen, even here in Santa Rosa. Click here to see an Example Of Lab Error, and here for Another Example Of Government Lab Problems. Moreover, if you took a blood test during the arrest process, the results may show a Problem Identified on Toxicology Report by the Department of Justice laboratory in Santa Rosa. For these and other credibility and reliability justifications, the government is required to retain your blood test specimen for one year at the Santa Rosa or Sacramento Department of Justice lab for retesting by you and your Sonoma County DUI lawyer at an independent lab if desired. Title 17 17CCR1219.1(f). Your Santa Rosa DUI lawyer can formally request a Sonoma County District Attorney authorization for retest, which is sent to the Department of Justice laboratory where a split sample of your blood is then sent to the lab of our choice for independent analysis.

Although this typically involves additional expense to you, nevertheless your Sonoma DUI attorney will explain to you that retesting can confirm blood type and DNA if there is a question whether the blood sample originally tested is in fact yours. Also, retesting can often lower the result number by .01 to .03 points, which may drop your result below .08 (or below .01 in the case of an under-21 zero tolerance DUI case) providing a better chance of a win at DMV, or additional assistance in plea bargaining efforts with the Sonoma County District Attorney to obtain a dismissal or reduction of charges, or avoid additional penalties for very high blood alcohol levels.

Click here to see a recent example of an independent lab analysis showing a New .07 Retest Result after retesting an initial .08 blood result from the Department of Justice. This effort, combined with a wet reckless bargain from the District Attorney, resulted in a complete victory at DMV and no driver license suspension at all for this client. Understand that all cases are unique and a blood retest in your case may not produce such victorious results, but some blood test cases benefit from a retest and other means for independently confirming or denying initial government assumptions and conclusions.

Hospital Draws.

If your blood was drawn by Santa Rosa hospital staff because paramedics or other authorized personnel were unavailable, or you were hospitalized due to injury, standard DUI blood draw techniques may not have been used (for example an alcohol swab may have been used to sterilize your arm). A local hospital draw can be challenged by a good Sonoma DUI lawyer if there is any suspicion that the results may be faulty due to incorrect blood draw procedures or that an unqualified individual performed the blood draw in your case. In addition, issues regarding patient-doctor confidentiality may arise and prevent the government's use of a Sonoma County hospital draw, particularly if the draw was not originally made pursuant to a request by a Sonoma County peace officer as required by the Vehicle Code. VC Section 23158(a). For a discussion about consulting with a Sonoma DUI lawyer regarding a hospital invoice for a blood draw before paying the bill, see this topic at the bottom of: Hire a Sonoma DUI Lawyer.

7. The 3-Hour Presumption

Police officers are never able to test your breath or blood alcohol precisely at the time you are driving. Your Sonoma County DUI lawyer will explain to you that typically at least 10-40 minutes elapse before you were tested, sometimes more than an hour or more subsequent to driving, particularly in remote accident cases and during busy holidays. Therefore the law provides the government with a legal fiction (a "presumption") that as long as the breath, blood or urine test samples are obtained within three hours of driving, the law will presume that the results obtained subsequent to the DUI arrest relate back to (were the same as) your alcohol level at the time of driving (Vehicle Code Section 23152(b)). If the test sample was not obtained within 3 hours, then the government cannot rely on this presumption and you may very well have a winning case in Sonoma County Superior Court and at the Santa Rosa DMV.

Understand that the 3-hour rule is a rebuttable presumption which may be challenged with our own affirmative evidence, introduced in a Sonoma County court or at the DMV, that even though the tests were obtained within three hours of driving, the tests are not an accurate reflection of your alcohol level at the time of driving. The best example is evidence of drinking after driving, even if the drinking happens in the vehicle once it has been parked and stopped. Good Sonoma DUI attorneys will tell you that one of the most common mistakes in such circumstances is denying this defense of drinking after driving at the time of arrest out of fear that admitting to drinking in a parked car would make things look worse to the arresting officer. See this discussion under Tip #4 above.

Time of Driving.

Obviously, in order to take advantage of this gift of a 3-hour presumption, the government (both the Sonoma County District Attorney and the Santa Rosa DMV) must be able to establish a time of driving with some degree of probability. Sonoma court and DMV cases may be winners if, for example, your Sonoma County DUI attorney can show that you were parked for more than a couple of hours, perhaps sleeping off some drinks, prior to encountering law enforcement, or you were involved in an an accident scene which remained undiscovered for a long time. Often your Sonoma DUI lawyer can use impartial witness testimony, bar receipts, phone messages, and cell phone records to establish driving outside three hours (see the Preserve Physical Evidence discussion in the Tips for the First 48 Hours articles on this site). Santa Rosa DUI attorneys can expect to encounter contrary government evidence of time-stamped dispatch records, evidence of the public visibility of an accident scene, evidence of recency of driving (you in the driver's seat, warm hood, keys in ignition, engine running, lights on), or records of an eye witness who may have called 911 to report erratic driving at a certain recorded time, all to challenge the defense argument that your vehicle had been stationary for a long time.

8. Chemical Test Refusals

The best Sonoma County DUI lawyers understand that if the police failed to obtain a sample of your breath, blood or urine, you may find yourself subjected to an allegation that you violated the implied consent law which requires that you provide such a sample pursuant to a valid arrest if Sonoma County law enforcement reasonably believed you were driving under the influence of alcohol or drugs, or else you may face certain penalties including loss of driving privileges for at least one year without the possibility of even a hardship or work license. (CVC 23612, 13353).

What Did The Officer Say?

Although the bottom line is whether you provided a sample or not, much of the legal focus may shift to the Sonoma County officer who alleged the refusal. Santa Rosa DUI attorneys want to see if the officer had reasonable cause to believe you were DUI. Precisely where and when did he/she request that you provide the sample, precisely what did the officer say when he/she asked you to provide the sample, and precisely what warnings were given to you regarding the consequence of failing to provide the sample?

Defending a Refusal Allegation.

Most refusal allegations are won when your Sonoma County DUI Attorney can establish to the court and the Santa Rosa DMV that the arrest was not valid, or that the police officer who made the arrest failed to warn you that you would lose your license for a year or more if you refuse to provide a sample, or that you were incapable of understanding the warnings due to injury, or due the arresting officer's misinformation. If you submitted to the preliminary alcohol screening test (PAS), which does not satisfy the legal requirement of a post-arrest test, still, sometimes it is possible that one or more factors may allow the Santa Rosa DMV to accept the preliminary results and "dismiss" the refusal allegation when Santa Rosa DUI lawyers properly present any compelling evidence existing in your case, to avoid the unforgiving minimum one-year license suspension.

Refusal allegations can often be plea bargained out of a court case in Sonoma County, but the Santa Rosa DMV rarely bargains and will still suspend your license for at least one year without allowing you to obtain a restricted work license, so Santa Rosa DUI attorneys understand that defending a refusal case at the DMV is critical to preserving your driving privileges. Click on the 2019 Refusal Form to see the principal form which Sonoma County DUI lawyers must fight at a Santa Rosa DMV hearing to try to protect your license. You can also see the older 2016 Form, or the 2012 Form, or the 2009 Form, and also the Under-21 Refusal Form

9. Necessity

Sometimes people feel compelled to drive while intoxicated in an emergency they are facing, or to help someone else, or in order to contend with, or escape from a dangerous situation. Santa Rosa DUI lawyers will explain to you that this is properly called an "equitable defense" which means it is based in consideration of fundamental fairness rather than written in a specific law. If successful, the defense can result in reduced or dropped charges in Sonoma County superior or traffic court, but such defenses are not typically recognized in the separate Santa Rosa DMV part of a DUI case.

These defenses are most successful when you identified the emergency at the time of the initial police encounter, and your Sonoma County DUI attorney can show the court independent facts which establish that the danger was of such a nature that there were no practical alternatives and even a sober, reasonable person would have been compelled to drive. In addition, in order to be successful with the equitable defense of necessity, typically you must have driven only so far as was necessary to escape the risk of danger or otherwise address the emergency. For example, if you were trying to get away from someone threatening your safety, then typically driving a couple of blocks or a mile or so would be the furthest expected and permitted.

10. Police Reports

The best Sonoma County DUI lawyers will explain to you that the Sonoma County court and the Santa Rosa DMV process are primarily fueled by the police report. The police report in a DUI case is not the end of the story, but it is certainly the beginning. A careful, detailed examination of Sonoma County police reports by an experienced Santa Rosa DUI attorney can often reveal numerous errors and/or omissions. Click here to see the most commonly used DUI police forms, titled the DS367 Age 21 And Older Officer's Statement (click here for the latest 2019 DS367 Officer's Statement, or here for the Older 2016 version, or here for the Older 2015 version, or here for the Older 2012 version, or here for the Older 2010 version, or here for the Older 2006 version), and the CHP 202 Driving Under The Influence Arrest - Investigation Report (click here for the latest 2017 CHP 202 Report, and here for the Older 2011 version).

Some errors and omissions are not legally significant (typos are human nature, right?), but others can be fatal to the government's case against you, especially at the Santa Rosa DMV where documents usually are the only evidence considered. If an important signature is missing at a critical place on a form, and the Santa Rosa and San Francisco DMV driver safety offices do not catch this error or omission in time to subpoena the responsible party to "fix" it at the local Santa Rosa hearing, then your Sonoma County DUI lawyer may be able to win your DMV case. Even numerous relatively minor errors may allow Santa Rosa DUI attorneys to call into question the reliability, credibility, and observing skill of the officer who made the DUI arrest, what we like to call the "Keystone Kops" defense.