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Blood Alcohol Concentration

When it comes down to it, DUI law centers around a driver's blood alcohol concentration. Blood alcohol concentration refers to the amount of ethyl alcohol in the bloodstream. When the concentration of alcohol gets too high, it hinders a driver's physical coordination, mental alertness, reaction time, critical thinking skills, and more.  When this happens, there is a much greater chance of the driver causing a serious or fatal accident.

In California, it is illegal to drive with a blood alcohol concentration of .08% or more. For people under 21, it is a crime to drive with a BAC higher than .01%. Anyone found driving with a BAC level that reaches or exceeds the legal limit will be arrested and charged with DUI.  In order to determine a driver's BAC, the arresting officer will conduct a breath or blood test.  If the results of the test indicate the driver's BAC is above .08%, then he or she will be arrested on DUI charges. It is also important to note that if a driver is on probation for a DUI, a blood alcohol concentration of .01% can trigger a driver's license loss and a probation violation in court.

Breath & Blood Testing in DUI Cases

Breath Tests:  Breath testing is the most common way police officers test BAC levels. To conduct a breath test, the officer, at the scene will instruct the driver to blow into a handheld device called a Preliminary Alcohol Screening device (PAS).  This, unless a person is on probation, or under 21 is an optional test. A second breath test is necessary to comply with state law. Breath alcohol testing devices, the ALCOTEST 7110 or 7410 (Drager), calculates the driver's BAC by measuring the amount of breath alcohol in the deep lung region, which is believed to have a direct correlation with the amount of alcohol in the bloodstream.

Blood Tests
: Blood testing is done either at the jail or a hospital, where a technician draws blood from the driver's arm for analysis. Although slightly less common than breath testing, blood testing is far more accurate, which can be a good thing if you're absolutely positive that your BAC is under .08%.  However, if you aren't sure if you are over the limit, or depending on the time of your last drink you may want to opt for a breath test, as those are less accurate and more prone to error. With blood testing you also have the option of having a sample sent to an independent laboratory for retesting.

DUI Defense in Alameda County, Contra Costa County and throughout the Bay Area

If you took a breath or blood test and failed, do not give up hope. There are still many viable defenses available to you. These tests are not 100% accurate, and error can easily occur. There are many circumstances or factors that could cause an inaccurate reading, such as:

  • Operator error
  • Radio frequency interference
  • Mechanical defects
  • Electrical malfunctions
  • Dirty/broken equipment
  • Weight and gender
  • Type of alcohol consumed
  • Eating before taking the test

Contact an Alameda & Contra Costa County DUI Lawyer

If you have been charged with DUI, and you took a breath or blood test, it's to your advantage to hire a skilled Contra Costa or Alameda County DUI attorney to defend you in court. Having been in this business for over 25 years, Attorney Lynn Gorelick has seen far too many people convicted of DUI because of breath or blood testing results.  Ms. Gorelick is committed to making sure this doesn't happen to you. She has a great deal of experience in DUI defense, and knows how to challenge the evidence submitted by the prosecution that suggests you are guilty.  Throughout her long career, Ms. Gorelick has helped many clients avoid a DUI conviction after failing a breath or blood test, and would be honored to do the same for you.  At the Gorelick Law Offices, protecting your best interest and providing you with aggressive defense are always Attorney Gorelick' top priorities.

Let Criminal and DUI Defense Attorney Lynn Gorelick, of the Gorelick Law Offices, Help.

Call Gorelick Law Offices at (510) 785-1444 or (925) 847-3006, and let Ms. Gorelick help you during this often uneasy, confusing, and frightening time! Trust an attorney with over 30 years of experience in the field of Criminal & DUI Defense - Lynn Gorelick.

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We offer a free initial consultation to people accused of DUI and criminal offenses in the Bay Area. Call us at 510-785-1444 to schedule yours.

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