Criminal Defense in Orange County
What are Breath & Blood Tests?

Breath & Blood Tests: Fighting the Evidence

DUI Defense Lawyer in Anaheim, CA

Woman Receiving Breathalyzer TestA chemical test, blood or breath, is the evidence of a person's actual blood alcohol level. These tests are usually very accurate, however, mistakes can be made. Even if these tests were 100 percent accurate, which they are not, they still do not show what the blood alcohol was at the time of driving. This must be done by a complicated process called retrograde extrapolation. At The Law Office of Barney B. Gibbs, our Anaheim DUI defense attorney knows this and also knows how the State and the Defense will present this.

Retrograde extrapolation is a complex mathematical process that is used to determine the level of intoxication not at the time of the test, but rather at the time of the arrest (while the subject was driving). If this process is calculated incorrectly, then the subject is at risk for showing a blood alcohol concentration at the time of arrest that is enough to warrant a conviction for driving under the influence. Our firm understands the intricacies of this mathematical equation, and will fight to see that the BAC evidence against you is accurate or else it must be dismissed.

Refusing a Chemical Test & License Suspension

Implied consent law states that whoever applies for and receives a driver license in the state of California also, by association, agrees to submit to a chemical test upon a lawful DUI arrest. It is important to remember that you are only required to submit to a breath or blood test if you have been lawfully arrested. If you refuse this type of chemical testing after a lawful arrest, then your license will go into automatic suspension. You may be able to fight this suspension if you schedule a DMV hearing within ten days of your arrest, but a license restoration is not guaranteed. At this administrative hearing, you will have to prove either that: a) you were not lawfully arrested, b)

Refusing a chemical test does not only mean outright saying "no" to a test, but also silence. If you are asked to submit to a chemical test but say nothing, then this will be considered a refusal to take the test. A refusal can also be failing to complete a breath or blood test (or a urine test in the case of DUI and drugs). If you at first agree to the test but then fail to follow through with the remainder of the breath, blood or urine sample, then this will be considered a refusal that would constitute a license suspension. If this is your first DUI arrest, then refusing a chemical test will warrant a one-year license suspension, if you are not successful at your DMV hearing.

PAS Tests (Preliminary Alcohol Screening Devices)

What are the PAS tests and are they part of the chemical tests that you have to submit to? The PAS tests are breath tests, but they are only preliminary tests much like the field sobriety tests. These tests can be administered before a lawful arrest. This means that you do not have to submit to them in order to keep your license, but it also means that you are still required to submit to an actual chemical test. Submitting to the PAS test, in other words, does not mean you no longer have to submit to a breath or blood test.

If you were arrested in Orange County for driving under the influence of drugs or alcohol, the breath and blood chemical test evidence will be used to convict your for this charge. It is our DUI lawyer's duty to fight to see that the evidence presented is accurate. This is why we test the chemical testing devices, the nature of the arrest and even look into how the test was administered. A false step could mean a dismissal of your charges.

Contact our team at The Law Office of Barney B. Gibbs for a free consultation!


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