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San Diego DUI Lawyer

Blood alcohol concentration (BAC) is the measurement of the percentage of alcohol in a person’s blood or on their breath. Alcohol is absorbed by the stomach and small intestine and then diffused into the blood, which then travels to the brain.

BAC testing is perhaps the most reliable form of evidence of a person’s level of intoxication, and this evidence often plays an important role in DUI cases. If a law enforcement officer has reason to believe you are drunk driving and stops your vehicle, you will be asked to submit to a breath or blood test to determine your BAC.

Under California law, a driver will be arrested for DUI if their BAC reaches the following limits:

  • BAC of .08% for a driver age 21 or older
  • BAC of .01% for a driver under the age of 21
  • BAC of .04% for a commercial driver
  • BAC of .01% for a driver on probation for DUI

The Effects of Alcohol on the Body

The impact of a person’s blood alcohol concentration is more severe the higher the percentage, as alcohol in the blood travels to the brain and impairs cognitive function. Alcohol will generally have the following effects on a person at each level of BAC:

  • .01% to .02% BAC: The person may experience subtle side effects from the alcohol which can only be detected after undergoing specialized tests.
  • .03% to .05% BAC: The person will have difficulty concentrating.
  • .06% to .09% BAC: The person’s ability to reason will be impacted, and their peripheral vision, glare recovery, and depth perception will be impaired.
  • .10% to .19% BAC: The person’s speech, gross motor control, reaction time, reflexes, and ability to walk will be impaired.
  • .20% to .29% BAC: The person will exhibit severe motor impairment, memory blackout, and lose consciousness.

What factors impact BAC?

BAC is the percentage of alcohol found in the blood, and though alcohol affects people in different ways, there are certain factors that can increase blood alcohol concentration in the body. If you have every wondered why some people become intoxicated more quickly than others, the reason is likely because of some of the following factors that affect impairment:

  • The individual’s gender
  • The individual’s weight and build
  • The amount of alcohol consumed
  • The length of time during which the alcohol was consumed
  • The strength of the alcohol
  • The carbonation of the alcoholic drinks
  • The amount of food consumed while drinking
  • Whether the individual was taking certain medications

How can BAC be lowered?

Contrary to popular belief, there is no trick to reducing blood alcohol concentration. While you may have heard that you can sober up by taking a cold shower, drinking coffee, or going for a run, the fact remains that the only way to reduce your BAC is to wait for your body to metabolize the alcohol, which can take a number of hours. If you are planning to drink, it is important to arrange for a designated driver or taxi to take you home after the night is over, because there is no shortcut to getting sober.

Blood Alcohol Concentration Testing

There are two main testing methods that determine a person’s BAC: breath and blood. The results of one of these chemical tests can be very important in a drunk driving case, so if you are stopped under the suspicion of DUI you will most likely be asked submit to a breath or blood test.

Breath Tests: This method of testing measures the amount of alcohol on a person’s breath and then uses the reading to estimate the percentage of alcohol in the blood. This method of testing is noninvasive, and to measure BAC through a breath test, the officer will have the driver breathe deeply into a Breathalyzer or similar breath machine. Although the results of a breath test are an indirect measurement of blood alcohol concentration, this evidence is considered to be valuable and can be very influential in a DUI case.

Blood Tests: Perhaps the most reliable method of measuring BAC (and the type of evidence most often preferred by law enforcement and prosecutors), blood tests involve analyzing a sample drawn from the person suspected of DUI. The driver’s blood will be drawn at the police station or a lab by a trained professional. The sample will then be analyzed by a qualified medical professional or technician to determine the percentage of alcohol in the blood. This testing method provides a direct measurement of an individual’s BAC.

Challenging Breath and Blood Test Evidence in San Diego

If you were charged with drunk driving based on the results of a breath or blood test, it is important to enlist the guidance of a San Diego criminal defense attorney as soon as possible. Your DUI attorneys in San Diego can determine if your rights were violated or if the results of your BAC test could have been tainted in any way by asking the following questions:

  • Did the officer have probable cause to stop your vehicle?
  • Were you observed for approximately 30 minutes before taking a breath test to ensure you did not vomit or burp?
  • Was the breath machine maintained regularly and correctly?
  • Was the breath machine calibrated correctly?
  • Was your blood sample drawn by a qualified and trained professional?
  • Did the technician use an alcohol-based swab to clean your skin before drawing a blood sample?
  • Was your blood sample labeled correctly?
  • Was your sample tainted in any way?
  • Was your sampled analyzed through standard and approved methods?

No matter the specifics of your case, it is imperative that you speak with experienced San Diego DUI lawyers before making any decisions about your charges. Contact The Law Office of Marc S. Kohnen today to discuss your defense options!

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Marc S. Kohnen

1350 Columbia Street, #700
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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