An Overview of BAC Tests in California DUI Cases

In the state of California, when a person is arrested under suspicion of driving under the influence (DUI), they will be asked to submit to a breath, blood, or urine test to determine their blood alcohol concentration (BAC). These tests are mandatory under the Implied Consent Law and can carry a lengthy driver’s license suspension and jail time upon refusal. With that being said, there are certain circumstances where refusing a test may actually be a wise decision.

What Are Preliminary Alcohol Screening Tests?

If you are ever pulled over or stopped at a DUI checkpoint, the officer may ask you to submit to a handheld breathalyzer test or some other type of physical sobriety tests such as a “walk-and-turn” test, a “one-leg stand” test, or a test of your horizontal eye movements. Known as preliminary alcohol screening (PAS) tests, these non-standardized tests are optional and are conducted solely for the purposes of helping the officer determine if there is enough evidence to arrest you for DUI.

While the officer may lead you to believe otherwise, if you have not been arrested, you do not have to submit to any sort of sobriety test and may refuse without penalty. Submitting to a PAS test can only hurt you later on down the line.

I Have Been Arrested – Should I Submit or Refuse?

If you have already been arrested, it is generally recommended that you submit to a test. While a test refusal may deprive the prosecution of evidence of your intoxication, the additional license suspension and jail time will most often only serve to worsen your situation. Furthermore, the prosecution does not need to be able to prove that your blood alcohol level exceeded the legal limit – only that you were intoxicated enough to be unfit to drive. Refusing a test is often used by the prosecution as evidence of guilt, thereby nullifying any benefit your refusal might have provided.

If given the choice, it is usually preferable to take a blood test over a breath test. Breath tests are less accurate and are more likely to register a false high reading than a blood test. With a blood test, two vials of blood will be drawn – one for the state, and one that you may have retested by a third-party laboratory at your own expense. It is not uncommon for the two samples to yield different results. An attorney can use this to contest the reliability of the state’s testing methods, such as by looking for signs of tampering, determining whether or not your blood was properly stored, or investigating if your blood sample was tested by an inexperienced technician.

Call Hanson, Gorian, Bradford & Hanich Today

If you have been arrested for driving under the influence or have been charged with refusing a breath test, the Murrieta DUI lawyers at Hanson, Gorian, Bradford & Hanich can provide the aggressive advocacy you need to protect your future and freedom. Call (951) 506-6654 or schedule a no-cost case review today to get started towards building your defense.


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