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DUI Blood Testing in California

Blood test is a popular method of measuring a driver’s blood alcohol concentration level (BAC) which serves as proof in driving under influence (DUI) charges. But this method can be subject to a number of flaws that can be contested in court. Title 17 of the California Code of Regulations specifies the protocols for DUI blood draws and testing. If these regulations are to comply with its letter, the findings of the blood test may be deemed invalid and could result in dismissal of your DUI charges.

The more common mistakes which lead to erroneous blood alcohol concentration ("BAC") results include contamination of the blood sample once it has been obtained, samples that have been switched or mixed, or alcohol production inside the vial due to fermentation, which may occur with the sample.

DUI Blood Test in California: When Mandatory

According to California's implied consent statute, any driver who has been lawfully stopped for a DUI must consent to a breathalyzer or blood test to ascertain their blood alcohol level. This so-called “implied consent law” is embodied in Vehicle Code section 23612.[California Vehicle Code 23612(a) (1) VC]

In most cases, drivers must be offered the option between a breathalyzer and a blood test. Exceptions may apply in the following circumstances, such as:

a) If the law enforcement officer has good reason to believe the driver was driving under the influence of drugs (DUID), a blood test may be necessary; [Vehicle Code 23612 (a)(2)(C)]

b) The driver is not awake (or has passed away); [ Vehicle Code 23612(a)(5] or

c) The device for breath testing is unavailable.

    DUI Blood Test vs. DUI Breath Test

    Note that in chemical testing, while it is mandatory, the method with which it shall be carried out, i.e., whether blood test or breath test shall ultimately be decided by the driver. There is no quick answer as to what type of test is better, though each test has its pros and cons.

    For most people, DUI breath test is preferred, being less intrusive, and yields quicker results as compared to blood testing. However, this method may not be ideal for some people, especially those who suffer serious medical conditions preventing them to perform the test properly, such as those suffering from asthma or emphysema. And, in some cases, breath test becomes impossible due to the unconscious state of the driver.

    However, it is not entirely impossible for some drivers to prefer DUI blood test as it offers their own advantages. Alcohol levels in the blood are directly measured by blood testing. With the use of a blood testing equipment, the amount of alcohol in deep lung air is calculated and mathematically translated into its equivalent blood alcohol concentration level.

    The conversion's formula, referred to as a "partition ratio," is predetermined by law. The partition ratio, however, varies from person to person. In this way, some individuals believe that blood test is a more reliable indicator of BAC than breath test.

    In addition to the foregoing, the main advantage afforded by choosing DUI blood testing is the availability of “Blood Split Motion” which can be used as a legal defense for DUI charges. With DUI blood testing, a portion of the blood test sample can be retained for independent testing by the driver. This will be discussed in more detail below.

    Title 17 of the California Code of Regulations

    Chemical tests for DUI are governed by Title 17 of the California Code of Regulations (CCR). Both broad specifications for testing labs and particular guidelines for blood tests are included in the statute.

    The more common regulations pertaining to blood testing under Title 17 include:

    a) The blood must be drawn by a designated technician or medical expert as soon as is reasonably practicable after the commission of the alleged violation. [17 CCR 1219.1(a)]

    b) To prevent adding external alcohol to the sample, the draw site must be disinfected using a method other than an alcohol-based product. [17 CCR 1219.1(b)]

    c) To avoid contamination and/or clotting, a vial must include both an anticoagulant and a preservative. [17 CCR 1219.1(d)(2)]

    d) Alcohol or other volatile organic solvents may not be used to clean or store any reusable equipment. [17 CCR 1219.1(c)]

    e) The sample's integrity and authenticity must be verified. [17 CCR 1219]

      The validity of the DUI blood test may be jeopardized if any of these procedures or others are not complied with, thereby casting doubt as to the accuracy of the results.

      Presumption of Validity of BAC results

      Once blood test is administered by law enforcement officers, the results yielded therefrom automatically enjoys the presumption of validity, i.e., the results were properly obtained. With the existence of this presumption, the burden of proving that procedures set forth under Title 17 CCR are observed is now borne by the defense. However, in some cases, even when Title 17 CCR procedures are not followed, blood test results are not automatically deemed invalid. This is especially true if there is no constitutional right violated in the process. [ People v. Esayian (2003) 5 Cal. Rptr. 3d 542]

      No Person Can be Forced to Undergo DUI Blood Test Except by Virtue of a Warrant

      In the case of Birchfield v. North Dakota [Birchfield v. North Dakota (2016) 579 U.S., 136 S.Ct. 2160], the United States Supreme Court declared that while the Constitution allows warrantless breath tests after a lawful arrest for drunk driving, the same principle does not hold true for blood test. There is no such thing as warrantless blood tests. In sum, the prevailing rule is that a warrant must be obtained in order to compel a person to take a blood test.

      Consequences of Chemical Test Refusal

      Refusal to take chemical tests is not necessarily a crime in California. However, refusal to take either blood or breath test following a lawful DUI arrest can result to an enhanced penalty, in the event of conviction for a separate crime of driving under the influence. In addition to the foregoing, the driver’s license shall be suspended by the California Department of Motor Vehicles, without due regard to the conviction or acquittal in the related criminal case.

      DUI Blood Sample Independent Testing

      Title 17 of the California Code of Regulations allows for independent testing of a blood sample by the driver. This is in furtherance of the driver’s right to file a “Blood Split Motion.” The motion involves DUI blood samples being split into two containers. By utilizing blood split motion, the driver is given the opportunity to test his blood sample independently; the ultimate purpose of which is to cast a doubt on the accuracy of the chemical test results conducted by the law enforcement authorities. To utilize this motion as a legal defense, the driver must seek the assistance of a defense lawyer who is experienced in the matter.

      Challenging DUI Blood Test Results

      Fighting DUI charges may seem an insurmountable task, but with the assistance of a skilled DUI defense attorney, this surely is possible. The approach to challenging DUI blood test results may vary on a case-to-case basis, depending on the unique set of facts. However, the more usual methods used by skilled California DUI defense attorneys to contest the results of blood tests for the crime include the following: (1) submitting a motion to strike the test results from the record; (2) aggressively contesting the findings of the police in an effort to obtain a DUI plea deal or a "not guilty" finding from the jury; and/or (3) rising blood alcohol defense.

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