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San Diego DUI Breath Testing

by | May 17, 2013 | Criminal Defense

The breath test is a method that law enforcement uses to determine a driver’s level of intoxication when suspected of a DUI offense. In California the legal blood alcohol concentration (BAC) that a person can drive with is below .08%, and anything above that is illegal and considered a DUI offense. To perform a breath test, the officer will have the driver breath into some type of breath machine. The breathalyzer is one device that measures the amount of alcohol on a person’s breath and uses this reading to estimate the percentage of alcohol in their blood.

Law enforcement generally uses a breathalyzer on the roadside when they suspect someone is alcohol impaired. If the instrument reads that the suspect’s BAC is over .08% then they can be arrested for a DUI offense; however, there is a level of uncertainty that comes with using the breathalyzer. The results vary depending on if the suspect holds their breath at all prior to exhaling, or if the suspect hyperventilates prior to exhaling then the margin of error is significant between results. Despite this uncertainty, failing a breath test will lead to DUI charges and this evidence can be very influential in court.

There are several ways to combat the breath test results, because there are non-alcohol related factors that can affect the results. Some of the outside factors are:

  • Your body’s composition
  • The environment
  • Errors in how the Law enforcement officer conducts the procedure

Physiological factors vary among each individual, but the instruments used for breath testing do not account for these differences. One example of a physiological difference is acid reflux; if a suspect has acid reflux, the mouth alcohol level may be affected, which could alter the results.

At the Law Office of Marc S. Kohnen, we are experienced in fighting drunk driving charges and knowledgeable in the various options available to challenge breath testing results. We are prepared to fight in court and show the faults of testing BAC with breath machine to help bolster your case. If you or someone you know has been arrested or charged with DUI after performing a breath test, contact a San Diego criminal defense attorney to help protect your rights.

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Marc S. Kohnen

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San Diego, CA 92101
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The information on this website is for general information purposes only. Nothing on this site should be taken as legal advice for any individual case or situation. This information is not intended to create, and receipt or viewing does not constitute, an attorney-client relationship.

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Contact The Law Office of Marc S. Kohnen if you have been arrested and charged with a crime and need a skilled San Diego criminal defense lawyer. The firm represents clients throughout the community, and you can learn about their services by visiting the Areas We Serve page.

Office of Marc S. Kohnen
1350 Columbia Street, #700
San Diego, CA 92101
(619) 398-2500

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