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DUI Blood Tests in California
A Quick Overview of DUI Blood Tests and Legal Limits in California
If you’ve been arrested for a DUI in California, you don’t have to face the criminal case and DMV consequences alone. At Geller Law, PC, we move quickly to protect your license, challenge the traffic stop and arrest, and attack the prosecution’s key evidence—especially breath or blood BAC test results—so you have the strongest possible defense from day one.
These cases often rely heavily on blood alcohol content (BAC) test results, which law enforcement uses to determine impairment.
Our team of skilled attorneys can carefully examine the entire process. Starting with the initial traffic stop and continuing through the lab’s handling of your sample, we aim to identify issues that could compromise the test’s validity.
Here’s what you need to know about how blood tests work, the legal limits in California, and how we help you fight back.
The Process of Blood Testing for DUI
Blood tests directly measure the concentration of alcohol in your bloodstream.
In California, a BAC of 0.08% or higher is generally considered legally impaired for non-commercial drivers. However, if you’re a commercial driver, 0.04% is enough to warrant a DUI charge.
For drivers under 21, any detectable amount can result in a violation. These numbers may sound straightforward. However, mistakes during the collection, handling, or analysis of your blood sample can produce incorrect or inflated results.
A DUI blood test generally follows a structured series of steps designed to measure your BAC as accurately as possible. When you are suspected of driving under the influence, a law enforcement officer may request that a trained medical professional—or a qualified phlebotomist—draw your blood. This procedure is often done at a police station or a nearby hospital.
- Once collected, the blood sample has to be properly labeled with your identifying information, sealed to prevent tampering, and transported under controlled conditions. Usually, the sample has to be refrigerated to prevent fermentation or decomposition that could artificially raise alcohol levels.
- The blood sample is then analyzed in a laboratory, typically using methods such as gas chromatography. This method measures alcohol concentration and may screen for other substances.
- If your results indicate you were “driving over 80” milligrams of alcohol per 100 milliliters of blood—or 0.08% BAC—you could face DUI charges.
- Finally, the lab writes a report listing its findings, which are sent to the prosecution.
However, just having a test result above the legal limit does not guarantee a conviction.
We can meticulously analyze the testing process and look for missteps that could undermine the credibility of the evidence.
PRACTICE AREAS
Legal Implications of Blood Test Results
Blood test results can play a big role in a DUI case. Prosecutors use them to argue your BAC was over the legal limit and that you were impaired. But a high BAC number doesn’t always tell the whole story about how you were actually driving or how you felt at the time.
Our duty at Geller Law, PC, is to show the court that lab results alone can be misleading if not properly contextualized. By examining your driving behavior or field sobriety test performance, we aim to refute the prosecution’s case.
As noted, under California law, driving with a BAC of 0.08% or higher can support a DUI charge. Yet, prosecutions may proceed even if your BAC is below 0.08%. This happens, especially if there is other evidence suggesting impairment, which might include:
- Field sobriety test performance
- Erratic driving
- Physical symptoms (slurred speech, bloodshot eyes, etc.)
- Officer observations
- Lower BAC readings that still show impairment
When we challenge blood test evidence, we can consult scientific professionals to ensure that lab procedures meet industry standards. We also keep track of any updates to DUI law.
Consent Laws Related to DUI Blood Tests
California operates under the doctrine of “implied consent.” By choosing to drive on California roads, you effectively agree to submit to chemical testing if you are lawfully arrested for DUI. This includes blood tests, breath tests, or sometimes both.
While you have the right to refuse a blood test, refusing can lead to serious consequences. The Department of Motor Vehicles may suspend your license for a year if you refuse, and the prosecution can use your refusal as evidence of supposed “consciousness of guilt.”
Nevertheless, some individuals may consider refusing, particularly if they feel law enforcement lacks probable cause or if the testing methods seem questionable. That’s where we step in.
Our role is to assess whether the police followed the correct procedures.
For example, we may ask if they read the implied consent warnings properly. It’s important to confirm whether officers had a valid warrant before forcing a blood draw after you refused.
Contact us right away after any suspected DUI stop. The choices you make early on can affect the outcome of your case. Rapid intervention by a skilled defense attorney may help prevent unconstitutional searches or unwarranted forced blood draws.
Challenging Blood Test Results in Court
When your future is on the line because of a DUI charge, challenging blood test results can be a game-changing step in your defense. We’re ready to examine every angle of the test for potential flaws or inconsistencies.
Several factors can undermine the prosecution’s claims:
- Chain of Custody: Your blood sample passes through multiple hands—from the official who draws it, to the individuals who transport it, to the lab technicians who test it. Any missed step or mistake in the process can affect how reliable the sample is. Paperwork errors or mishandling can also raise serious doubts about the test results.
- Testing Procedures: Labs use testing methods to measure your BAC. These tests are known to be accurate, but mistakes can still happen. Errors such as poor machine calibration, expired chemicals, or misread data can skew the results. We review the lab’s process closely to find these weak points.
- Qualifications of Lab Technicians: The specialized nature of blood-alcohol testing means labs are required to hire well-trained personnel. If the technician lacks proper training or has a history of mistakes, it can strengthen our claim that your results may not be valid.
- Medical or Physiological Factors: Certain medications or medical conditions, like certain antacids or having diabetes, can impact how quickly alcohol is absorbed. We can consult medical professionals to determine which external factors may have influenced your BAC.
- Rising BAC Defense: BAC is not a static figure—it changes continuously as your body processes alcohol. We sometimes argue that your BAC was under the legal limit at the time you were driving, even though it rose above the limit by the time the test was administered. This line of defense, known as the “rising BAC” defense, requires precise timing, evidence, and professional testimony.
Over the years, we have successfully challenged blood test results in numerous DUI cases, sometimes leading to reduced charges or outright dismissals. Our approach combines meticulous attention to detail with aggressive advocacy.
Geller Law, PC: Your Partner in DUI Defense
At Geller Law, PC, we understand you need a committed defense team that knows how to challenge test results. Furthermore, we can represent your interests in negotiations and, if necessary, before a judge or jury.
We believe knowledge, combined with a detailed approach to each case, is crucial in facing DUI charges effectively. While we cannot promise a specific result, our thorough investigation can uncover weaknesses in the prosecution’s case, giving you a stronger footing during negotiations or at trial. Moreover, we use our years of courtroom experience and a relentless focus on detail to fight for the best possible outcome on your behalf.
If you or someone you know is facing DUI charges in California, do not hesitate to reach out.
We’re here to answer your questions and support you through every step of the process. When you hire us, you can expect clear updates, strong protection of your rights, and fast action to build a robust defense.
Contact us today, and let our team of experienced DUI defense lawyers protect what matters most to you—your freedom, your reputation, and your peace of mind.
- 1. What is a DUI blood test in California?
- 2. When can police require a blood test instead of a breath test?
- 3. Do you have to agree to a blood test if an officer asks?
- 4. What are the consequences of a blood test showing impairment?
- 5. Can blood test results be challenged in court?
A DUI blood test is a chemical test conducted to measure the amount of alcohol or drugs in a person’s bloodstream after they are suspected of driving under the influence. Law enforcement may request or order a blood test when there is reason to believe impairment from alcohol or drugs.
Police may choose a blood test over a breath test when they suspect the presence of drugs (including prescription or illicit substances) that a breath test cannot detect, or when a breath test is unavailable or unreliable. In some cases, officers may obtain a warrant to draw blood if the driver refuses testing.
Under California’s implied-consent laws, drivers automatically agree to chemical testing (breath or blood) by choosing to drive. Refusing a blood test when lawfully requested can lead to administrative penalties like license suspension, even if you are not criminally convicted.
If a blood test shows a blood alcohol concentration (BAC) above the legal limit, or detects impairing drugs, it can be used as evidence against you in a DUI case. This may lead to criminal charges, fines, license suspension, and other consequences depending on your record and the test results.
Yes. Results from a blood test can be challenged on various grounds, such as how the sample was collected, handled, stored, or tested. Challenges may argue that procedures were not followed, contamination occurred, or that the testing equipment was not properly maintained. Effective legal review can impact how blood evidence is used in your case.