Dedicated DUI Defense Attorney Backed by More Than 20 Years of Legal Experience

Blood Alcohol Testing

Blood alcohol tests are administered by law enforcement to people who are suspected of driving under the influence. These tests are used to determine the person's blood alcohol concentration (BAC), which informs law enforcement of how much alcohol is in the person's bloodstream. Law enforcement can determine a person's BAC through a breath, blood, or urine test. In California, a person is considered intoxicated by legal standards if his or her BAC is 0.08% or higher.

It is important to remember that the blood alcohol test is supposed to determine the blood alcohol concentration during the time the driver was operating his or her motor vehicle, not the person's BAC after the fact. This means there can be a significant difference between a driver's BAC at the time of driving and the driver's BAC at the time the test is taken.

Blood alcohol tests play a crucial role in all DUI cases. In many instances, it is the person's BAC that leads law enforcement to make an arrest in the first place. The BAC also plays an important role in the person's criminal case proceedings and DMV hearing.

Additionally, if the person's BAC is 0.08% or greater, his or her license will automatically be suspended by the police. For this reason, BAC test results must always be questioned. Even the slightest error can lead to life-altering legal consequences if the person is convicted of DUI.

Like all tests, BAC tests are prone to great error. For example, breath alcohol tests can be inaccurate if the person used mouthwash or consumed food prior to taking the test. It is also important to know the conditions in which all BAC tests are administered, who administered them, and if the people administering the tests were certified to do so.

All too often, inaccurate BAC test results lead to false convictions. For this reason, it is advantageous for a person to hire an attorney immediately after his or her DUI arrest. An attorney can investigate the results of a person's BAC test, question the people who administered the tests, and find any hidden errors that may have negatively influenced test results.

Marin County DUI Attorney

Attorney Robert Tayac has helped clients from all throughout Marin County combat their DUI charges with much success. Mr. Tayac is a reputable and understanding attorney, who is extremely knowledgeable when it comes to DUI law. Unlike other attorneys, Robert Tayac's primary focus is DUI law. His years of DUI practice experience and winning track record speak for him.

As a well-qualified DUI Attorney, Mr. Tayac is dedicated to his clients' needs and to producing outstanding results on their behalf. With professional DUI Attorney Robert Tayac on your side, your chances of successfully fighting your charges and avoiding a conviction in Marin County will greatly increase.

Marin County DUI lawyer Robert Tayac represents people arrested in the following communities:

Belvedere, Bolinas, Corte Madera, Dillon Beach, Dogtown, Fairfax, Greenbrae, Inverness, Inverness Park, Kentfield, Lagunitas-Forest Knolls, Larkspur, Marin City, Marshall, Mill Valley, Muir Beach, Nicasio, Novato, Olema, Point Reyes Station, Ross, San Anselmo, San Geronimo, San Rafael, Sausalito, Stinson Beach, Tiburon, Tomales, Woodacre.

Contact the Law Office of Robert Tayac for your free case evaluation!

Why Choose Our Firm?

Attorney Robert Tayac Puts a Long, Decorated Career to Work for You
  • Puts Over 20 Years of Experience Toward Your Case

  • Specialized Education in DUI Defense

  • Has Trained Other Attorneys in San Francisco

  • Former San Francisco Police Officer & Police Inspector

  • Certified by the SFPD on the Intoxilyzer 5000 Testing Device

  • Co-Authored the 4th Edition of California Drunk Driving Defense

  • Boasts a Successful Record Achieving the Best Result for His Clients

  • Takes the Time to Understand You & Your Case

Client Testimonials

  • “Without Mr Tayac's knowledge and drive to succeed, I most likely would not be able to write this review today.”


  • “I do recognize that you achieved for me an outcome exceeding what is typical for Santa Clara County.”


  • “My family and I cannot thank you enough...”


  • “His in depth knowledge and expertise within his field, along with deep and lasting relationships with the District Attorneys office and everyone involved are without a doubt unmatched.”


  • “These clients have called me to thank me for referring them to the Law offices of Robert Tayac.”

    R.R., Attorney at Law

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