Blood, Urine & Breath Tests for DUI

At The Law Offices of Michael L. Davidson, our DUI defense attorneys in San Mateo put a science background to work for our driving under the influence clients. The alternatives of blood and alcohol testing are imperfect, although a lawyer’s ability to challenge their validity is somewhat limited in court. If you have been accused of DUI in the San Francisco Bay Area, call 650-573-8000 to reach a lawyer to discuss your case–it can mean the difference between conviction and exoneration.

Which DUI Test to Choose: Blood, Urine or Breath

As part of California’s implied consent law, if you are accused of drinking and driving, you must consent to an evidentiary blood or breath test. This does not mean that you necessarily have to submit to a field sobriety test, however. Now the question is, what DUI test should you choose? Blood, urine or breath?

Urine Tests

Urine tests are not effective means to measure blood alcohol content, and are no longer used in California for that purpose. If an officer suspects that you are driving under the influence of drugs? San Mateo Lawyer you may be asked to take a urine test. Do not volunteer for a urine test; however, do not refuse a urine test if asked to submit to one.

Blood Tests

Blood tests are the most direct, and hence most accurate, measure of blood alcohol levels. Because a blood test allows for multiple tests of the same sample, it is more accurate. If you know that you are intoxicated, do not volunteer to take a blood test, especially if you have already had a field breathalyzer test, as it will only reinforce the District Attorney’s case. However, if you are sure that you are not intoxicated but have been brought in under suspicion of DUI, its accuracy will work in your favor and prove the breath test wrong.

Breath Tests

A breath test is the most common field sobriety blood alcohol test. Unless it is an evidentiary breathalyzer machine (E-pass) which is mandatory, we do not recommend you volunteer to take it–or any–field sobriety test if you are intoxicated. At the police station, however, if you are certain that you are legally intoxicated, a breath test may be your best option. It is easier to challenge the validity of the breathalyzer because there is a greater likelihood for a faulty test.

Contact a DUI Lawyer Today!

If you are stopped in the Bay Area, it is most important to contact a San Mateo DUI Defense attorney to discuss these issues before consenting. Our attorneys proudly represent clients throughout the entire Bay Area including these cities on the Peninsula:

  • San Mateo
  • Redwood City
  • Foster City
  • San Bruno
  • South San Francisco
  • Palo Alto
  • Burlingame

Call The Law Offices of Michael L. Davidson at 650-573-8000 or email us today.

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The Law Offices of Michael L. Davidson
411 Borel Avenue
San Mateo, CA 94402

Phone: 650-573-8000
Fax: 650-345-9875
San Mateo Law Office