Challenging a Breath Test

If you have been charged with drunk driving based on the results of a breathalyzer or other breath test, your DUI attorney may be able to defeat the charges against you and protect your driver’s license by showing that the results of the test are not reliably valid.

Challenging a Breath Test With in San Mateo

At The Law Offices of Michael L. Davidson, we have more than 40 years of experience helping clients challenge the results of California breath tests. Based in San Mateo, we have defended thousands of clients throughout the Bay Area against DUI charges. Call 650-573-8000 or contact us online.

Asking Important Questions About Your Breath Test Results

If you hire us to represent you, our attorneys and investigators will evaluate the results of your breath test to determine whether we can challenge them at a DMV hearing or in conjunction with your criminal DUI case. We will carefully follow up on issues like the following:

  • Was the person who administered the test properly trained?
    • There are several different breath testing machines used in California. People who administer breath tests need specific training in order to operate these complex machines correctly.
  • Was the machine cleaned and calibrated recently?
    • All breath test machines must be kept in good working order in order to produce accurate results. That includes cleaning and calibration, which must take place according to a strict schedule.
  • Were you observed for 15 minutes before the test?
    • Under California law, a breath test subject must be continuously observed for 15 minutes before the test is performed to ensure that he or she does not ingest fluids, regurgitate, vomit, eat or smoke.
  • Were there any factors that could have affected the reading?
    • Breath tests estimate blood alcohol on the basis of breath. These estimates can be significantly thrown off by factors such as obesity, chemical exposure and certain medical conditions.

Contact a San Mateo DUI Attorney Today!

Our experienced DUI defense lawyers have helped thousands of clients fight and defeat DUI charges. Our DUI 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

To schedule a free consultation to discuss your breath test results, call us at 650-573-8000 or send us an e-mail 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