DUI (Driving Under the Influence) breath and blood tests play a crucial role in determining the level of impairment caused by alcohol or drugs in drivers. These tests are used by law enforcement authorities to measure a driver's blood alcohol concentration (BAC) and gather evidence for potential DUI charges. While breath and blood tests are commonly employed methods to determine intoxication levels, these tests are not always accurate or admissible evidence for DUI charges. As a result, you can base your DUI defense on challenging the result or manner these tests were conducted.

If you have been arrested or charged with DUI in Bakersfield, we invite you to contact us at Koenig Law Office. We specialize in DUI defense and have a deep understanding of the various errors that can arise from breath and blood tests, from which we can build a defense strategy to challenge your DUI charges.

California Implied Consent Law in Relation to DUI Chemical Tests

The California implied consent law is a principle that applies to individuals who operate motor vehicles on California's roads. Under Vehicle Code 23612, by driving in the state, individuals are deemed to have consented to chemical testing (such as breath, blood, or urine tests) to determine their blood alcohol concentration (BAC). This law only applies to drivers who have been lawfully arrested.

This law is based on the understanding that driving is a privilege and that the state has a legitimate interest in ensuring road safety by deterring and penalizing impaired driving. By obtaining a driver's license and driving on public roads, individuals implicitly agree to comply with the implied consent law.

After a DUI checkpoint or traffic stop, an officer can request you to submit to a chemical test to determine your BAC. The specific type of test (breath, blood, or urine) may depend on factors like the circumstances of the arrest, availability of testing equipment, and any medical conditions that may affect the choice of test.

Refusing to submit to a chemical test after a lawful arrest can have significant consequences. The most common penalty for refusal is the automatic suspension of the driver's license. For drivers without a prior DUI, the license suspension period is one year, 2 years for drivers with one DUI prior, and 3 years for drivers with 2 or more DUIs. In addition to driver’s license suspension, a driver will face the following additional sentences for refusal to take a breath or blood test:

  • 48 hours in county jail for first-time offenders.
  • 96 hours in county jail for second-time offenders.
  • 10 days in county jail for third-time offenders.
  • 18 days in county jail for fourth-time or subsequent offenders.

DUI Breath Tests

Drivers will likely undergo two breath tests: Preliminary Alcohol Screening (PAS) Test and Evidentiary Test.

The Preliminary Alcohol Screening Test

This test is typically administered at the roadside, following a traffic stop, or when a driver is suspected of driving under the influence. The primary purpose of the PAS test is to provide law enforcement officers with an initial indication of whether a driver has alcohol in their system. It helps officers assess whether there is probable cause to proceed with further testing or to make an arrest for DUI.

The devices used for the PAS test are portable and designed for field use. They are handheld devices that employ various technologies, such as infrared spectroscopy or fuel cell technology, to detect and measure the alcohol content in the breath sample. The most common devices used are Breathalyzers or Intoxilyzers. The officer will request the driver to blow into the device, which analyzes the breath sample to estimate the BAC.

The PAS test results are generally not admissible as evidence in court proceedings. These preliminary tests are considered screening tools rather than definitive measures of a person's BAC. They serve as an initial indicator for law enforcement to make informed decisions during a DUI investigation.

A driver can refuse to submit to a PAS test unless they are:

  • Underage drivers (drivers under 21) — Zero tolerance and underage DUI laws waive the right of drivers to refuse a chemical test.
  • On Probation — Drivers on DUI probation cannot refuse a chemical test.

As a field sobriety test, refusal to submit to a PAS test does not carry any penalty for adult drivers and those that are not currently under DUI probation.

The Post-Arrest Test

Also known as the “evidentiary” test, the post-arrest test is mandatory for drivers who have been lawfully arrested for driving under the influence. The purpose of the evidentiary breath test is to provide more precise and reliable BAC measurements for legal proceedings. It is typically administered at a police station or other designated testing location by trained personnel, such as law enforcement officers or breath test technicians.

You are required to submit to this test even if you have taken a PAS test. At this stage, you may choose a breath or blood test unless:

  • You have a medical condition that prevents you from providing an adequate breath sample. For instance, a breath test may not be feasible if you have a respiratory condition or injury. In such situations, a blood test may be the alternative chosen to determine the driver's BAC.
  • You are unconscious or incapacitated, in which case a breath or blood test may not be an option.
  • There is no access to a functioning or approved breath-testing device. This can occur if the device is not readily available (for example, if you are taken to a medical facility where a testing device is unavailable) or if it is inoperable.
  • The officer reasonably believes you were driving under the influence of drugs. In this case, a blood test is required since breath tests cannot determine the presence of drugs in your body.

Title 17 Regulations for DUI Breath Tests

The California Code of Regulations, Title 17, includes several regulations that govern the administration and procedures of breath tests for DUI cases in California. Here is a list of some key Title 17 regulations relevant to DUI breath tests:

  • Breath-testing devices must be approved by the State Department of Public Health (DPH) before they can be used for evidential testing. Approved devices must meet the DPH's standards for accuracy, precision, and reliability.
  • Breath-testing devices must be calibrated at least once every 10 days or every 150 tests, whichever comes first. Calibration must be performed according to the manufacturer's instructions and using a calibration standard traceable to the National Institute of Standards and Technology (NIST). Calibration records must be maintained, including the date, time, operator, and results of calibration.
  • Accuracy checks must be conducted on breath-testing devices using an external standard solution that simulates a specific BAC level. Accuracy checks must be performed before and after each subject test or calibration, or at least once every 31 days, whichever comes first.
  • Breath-testing devices must undergo regular maintenance as specified by the manufacturer. Any necessary repairs or replacements of components must be performed promptly by authorized personnel. Detailed records of maintenance and repair activities, including dates, actions taken, and personnel involved, must be maintained.
  • Operators of breath-testing devices must complete a training course approved by the DPH. The training covers topics such as device operation, sample collection, testing procedures, and quality control measures.
  • Breath samples for testing must be collected in a manner that ensures the sample's integrity and prevents contamination. Operators must visually observe the subject for at least 15 minutes before obtaining a breath sample.
  • Breath test results must be reported on a standardized form provided by the DPH. The form includes information such as the subject's identifying details, test location, device used, test result, and operator information. Any discrepancies or issues related to the testing process must be documented and reported appropriately.

Factors Influencing Breath Test Results

  • Mouth Alcohol: The presence of residual alcohol in the mouth, such as from recent consumption or belching, can lead to artificially high breath test results.
  • Breath Temperature: The temperature of the breath can affect the accuracy of the breathalyzer device. Cold or hot breath may produce unreliable readings.
  • Breathing Patterns: Irregular breathing patterns, such as shallow breaths or hyperventilation, can influence breath test results.
  • Instrument Calibration: Improper calibration or maintenance of the breathalyzer device can lead to inaccurate readings.

DUI Blood Tests

Blood tests play a crucial role in determining a person's blood alcohol concentration (BAC) or the presence of drugs in their system. Compared to breath tests, blood tests offer greater accuracy and reliability, making them an essential tool in prosecuting and defending DUI charges.

When a driver is suspected of driving under the influence, law enforcement officers may opt for a blood test if a driver refuses to take a breath test or is physically unable to provide an adequate breath sample. This situation may arise when a driver has a medical condition, such as respiratory issues, or when a breath-testing device is unavailable or malfunctioning.

Blood test results are generally presumed accurate and properly obtained. Therefore, the defense has the burden of showing Title 17 regulations were not complied with. Here is how the test is done:

  • The draw site, typically the inner elbow area, is cleaned and sterilized using a substance other than an alcohol-based product. This is to avoid any external alcohol contamination of the sample.
  • The medical professional gathers the necessary equipment, including a sterile needle, vacuum-sealed blood collection tubes, anticoagulants, and preservative vials. The tubes and vials may contain additives to prevent clotting and preserve the sample's integrity.
  • The medical professional examines the individual's arm to locate a suitable vein for blood collection. A tourniquet may be applied above the intended draw site to enhance vein visibility and engorgement.
  • The medical professional inserts the sterile needle into the selected vein. Blood is collected into the vacuum-sealed tubes or directly into the anticoagulant and preservative vials. Multiple tubes or vials may be filled to provide sufficient sample volume for testing.
  • The medical professional gently mixes the blood with any additives present in the tubes or vials to prevent clotting. Each tube or vial is labeled with identifying information, including the individual's name, date, time, and unique identification numbers.
  • The collected blood sample is carefully handled to avoid contamination or damage. It is placed in a secure and appropriate storage container to maintain its integrity during transportation to the testing facility.
  • The entire process, from blood collection to transportation, is meticulously documented to maintain the chain of custody. This includes recording the names and signatures of all individuals who handle the sample, along with the date and time of each transfer.
  • The blood sample is sent to a certified laboratory for analysis by forensic scientists or medical technologists. The laboratory uses specific analytical methods to measure the alcohol concentration or detect the presence of drugs in the sample.

Factors that Can Influence Blood Test Results

  • Contamination: Contamination of the blood sample can occur during collection, handling, or storage, potentially leading to erroneous results.
  • Hematocrit Level: The hematocrit level, which measures the proportion of red blood cells in the blood, can affect the blood alcohol concentration (BAC) measurement. Higher or lower hematocrit levels may impact the accuracy of the result.
  • Preservatives and Anticoagulants: The presence or absence of proper preservatives and anticoagulants in the blood sample collection vial can impact the integrity and stability of the sample.
  • Analytical Method: Different analytical methods employed by laboratories may yield varying results. It's important to ensure that the chosen method is reliable and recognized in the field.

Challenging DUI Charges Based On DUI Breath and Blood Tests

Challenging the validity and accuracy of DUI chemical tests is one of the best ways to have your charges reduced or dropped altogether.

Violation of Constitutional Rights

An illegal stop, improper search & seizure, or lack of probable cause for the DUI arrest is a violation of your constitutional rights. These violations can impact the admissibility of the breath or blood test results as evidence.

Improper Administration of the Test

A defense strategy may involve challenging the proper administration of the breath or blood test. This can include questioning whether the test was conducted by a qualified technician or medical professional, whether the proper protocols were followed, or whether your rights were violated during the testing process.

Accuracy and Reliability of the Test

Challenging the accuracy and reliability of the breath or blood test results is a common defense strategy. This may involve questioning the calibration and maintenance of the testing equipment, potential contamination of the samples, or procedural errors during the collection or analysis process.

Rising Blood Alcohol Defense

It is possible that your BAC was below the legal limit while driving but increased to an illegal level by the time the test was administered. This defense is based on the delay between the time of driving and the time of testing, during which alcohol absorption may occur.

Medical Conditions or Interference

If you have a medical condition that could affect the accuracy of the test results, such as acid reflux, GERD, or diabetes, it may be argued that the medical condition interfered with the breath test accuracy. Similarly, certain medical conditions or medications may be used to challenge the validity of blood test results.

Independent Testing

DUI testing laws require a driver’s blood sample to be stored for independent testing. You may seek to have this blood sample independently tested by your own expert to challenge the prosecution's results. This can help identify any potential errors or inconsistencies in the initial testing process.

Are There Alternative DUI Chemical Tests?

A urine test is an alternative test for DUI breath and blood tests. Urine tests are commonly used for drug testing purposes, including in the context of employment screenings, probation monitoring, and other situations where drug use needs to be detected. In the context of DUI laws, urine tests are used in driving under the influence (DUID) investigations.

Unlike urine tests, blood tests are generally more accurate for detecting the presence of drugs or alcohol. These because blood tests can directly measure the concentration of drugs or their metabolites in the bloodstream, thereby providing a more immediate and accurate representation of recent drug or alcohol use. As a result, blood tests are the most preferable DUI chemical testing methods.

Find a Bakersfield DUI Defense Attorney Near Me

While DUI breath and blood tests are a foundation for DUI arrests and charges, they play a crucial role in preparing a defense strategy. You can challenge the validity of the test results, thereby making the resulting evidence inadmissible. You can also challenge the accuracy and the way the tests were conducted, which can result in reduced or dismissed charges. Either way, you need an expert DUI defense attorney to analyze the test procedure and results, and challenge any resulting DUI charges.

We at Koenig Law Office have a specialty in defending people facing DUI charges throughout Bakersfield. We can analyze the BAC results resulting from your chemical test and devise a strategy to challenge these results. Get in touch with us at 661-793-7222 to learn more!