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Choosing the Right Blood Alcohol Test

Should you take a blood test or a breath test if you get pulled over by a police officer on suspicion of driving under the influence? What about taking a blood or breath test at the police station? It is important to know your rights and know what options you have if you have been stopped on suspicion of driving under the influence. Choosing the right blood alcohol test can be important when building your defense.

Choosing a Breath Test

Preliminary Alcohol Screening Test: Should I agree to take a preliminary alcohol screening test (after being stopped) if requested by a police officer? Police officers are not required to explain to a suspected impaired driver that this screening test, which determines one’s alcohol level closest to the time of driving, is not required by law. In most circumstances this test should not be agreed to. This is because it provides the police with additional negative evidence, which may confirm the accuracy of a subsequent breath or blood test. The only exception to the general rule of not taking the test would be if a person only had one drink or did not drink at all and their blood alcohol would clearly be under the legal limit.

Should I choose to take a breath test to determine my alcohol level (typically at the police station)? California Vehicle Code Section 13353 requires a person who is suspected of driving under the influence to submit to a blood alcohol test (breath or blood). There is a difference between the preliminary test and the test at the police station. The preliminary test is done in the field using a small handheld device and it is not required. The blood alcohol test at the police station is required and it is usually done with a bigger machine that is plugged in. It is Hoffman & Associate’s general legal advice to submit to a breath test at the police station to determine one’s alcohol level. In contrast to blood, breath testing has an acceptable .02 variance. This possible acceptable margin of error means that if your tested blood alcohol was .08, in truth you may have actually had a blood alcohol of .06 or .10. It is always better to have a less accurate test that is being used against you as evidence versus a more accurate test. This variance range is good for the defense of a DUI case and it allows for better negotiation and a better defense strategy should the case go to trial.

Choosing a Blood Test

What are the pros and cons of taking a blood test? Typically, where a breath test is administered at the station, a blood test is frequently given at a hospital. This requires the suspected impaired driver to be transported from the police station to the hospital and then back to the police station which can create additional time delays on a person’s release. Blood tests have been found to be more accurate than breath tests. As a result, blood tests do not have the same range of marginal testing error as a breath test has. Prosecutors typically view blood test results as stronger evidence of an accurate blood alcohol test and are often less negotiable on blood tests versus breathe tests.

Refusing to Take a Test

Should I refuse to take any chemical test? Traditional views dating back many years viewed it as more favorable to not supply the prosecutor with more evidence against a suspect drunk driver. Not having a chemical test result whether breath or blood to use against a suspected impaired driver would clearly be a weakness in the prosecutor’s case. But, years ago the legislature added California Vehicle Code Section 13353 which created substantially increased penalties for anyone who does not submit to a breath or blood test. These consequences include a substantially harsher license suspension from the DMV in addition to mandatory jail time from the courts, which is not required for even a person driving with a very high blood alcohol level who submitted to a chemical test. Additionally, California Vehicle Code 13353 also suggests that prosecutors should increase the length of a first offense DUI alcohol program from 3 months to 9 months for any driver that refuses to submit to a chemical test.

The relevant section of California Vehicle Code Section 13353 provides that:

  1. If a person refuses the officer's request to submit to, or fails to complete, a chemical test or tests pursuant to Section 23612, upon receipt of the officer's sworn statement that the officer had reasonable cause to believe the person had been driving a motor vehicle in violation of Section 23140, 23152, or 23153, and that the person had refused to submit to, or did not complete, the test or tests after being requested by the officer, the department shall do one of the following:
    1. Suspend the person's privilege to operate a motor vehicle for a period of one year.
    2. Revoke the person's privilege to operate a motor vehicle for a period of two years if the refusal occurred within 10 years of either (A) a separate violation of Section 23103 as specified in Section 23103.5, or of Section 23140, 23152, or 23153, or of Section 191.5 or subdivision (a) of Section 192.5 of the Penal Code, that resulted in a conviction, or (B) a suspension or revocation of the person's privilege to operate a motor vehicle pursuant to this section or Section 13353.2 for an offense that occurred on a separate occasion.

If you have been arrested on suspicion of driving under the influence you should contact an experienced attorney, like those at Hoffman & Associates, as soon as possible to begin preparing you defense.