Attorney Discusses BAC Testing in San Diego
Speak with a San Diego DUI Defense Attorney About Your Test Results
Blood alcohol concentration (BAC) refers to the amount of alcohol within one’s bloodstream. A person’s BAC is shown as a percentage and indicates their level of intoxication, and consequently, their inability to drive. Law enforcement officers who are suspicious of a driver’s ability to drive may request the suspect to take a sobriety test to determine his or her level of impairment. These types of tests, however, do not accurately measure one’s BAC, so the results cannot always fully be trusted.
Generally, a BAC of 0.08% or higher is enough to arrest a person for drunk driving—as this is the legal limit in California. However, there is no single formula that will definitively lead to this BAC level, as everyone's body reacts differently to the amount of alcohol consumed. Blood tests that reflect a person's blood alcohol concentration are the most objective way to determine an individual's level of impairment, and therefore they are widely used as factual evidence in court.
If you have been arrested or charged with DUI due to an illegal BAC, it is crucial to seek the help of a San Diego DUI lawyer as soon as possible. Call our firm at (760) 630-2000 to get representation!
About Breath Tests
Breath tests measure the content of alcohol in the breath. Then the breath measure is multiplied by a factor to determine the blood alcohol content (BAC). What many people do not know about breath tests is that they are only an indirect measure of BAC and are often prone to error. As the BAC is not directly measured by a breath test, the breath test only approximates the BAC. For this reason, it is highly advised that you do not accept defeat as soon as you have been arrested, but rather take the initiative to challenge such evidence.
Factors that can make the breath test read too high include:
- Physical condition of the defendant
- Colds and fever
- Belching or vomiting prior to testing
- Mouthwash and dental adhesives
- Food eaten before testing, particularly bread
- Temperature (cold air increases the reading)
- Failure to calibrate the breathalyzer
About Blood Tests
Blood tests are one of several methods that law enforcement can employ to determine whether or not you are under the influence of alcohol or drugs while operating a motor vehicle. Blood tests are usually only administered, however, in extreme circumstances, such as when you have been hospitalized due to an accident. If the complex regulations involved in blood testing are not followed exactly, a skilled criminal defense attorney can move to have the evidence of any blood test suppressed. If the evidence is suppressed it cannot be used against you in a court of law. This often results in the charges against you being dropped, as the blood or breath test results are often the main pieces of evidence in a case.
Some of the following are examples of violations:
- Failing to administer the blood test correctly
- Contaminating or switching the test results
- Waiting too long to administer the test, allowing your BAC to rise inaccurately
- Failing to get a legal search warrant for the test or your explicit permission
Can I Challenge BAC Test Results?
If you have been arrested for DUI in San Diego after providing a breath or blood sample that was measured at a 0.08% BAC or higher, it is important to understand that this does not automatically prove your guilt. There are a number of ways in which a law enforcement officer can make a mistake while administering a sobriety test, as well as a variety of unrelated factors that could contribute to a skewed BAC reading (as explained above), so you should not hesitate to challenge such evidence.
By enlisting the help of our San Diego DUI attorney, you can rest assured knowing your case is in capable hands. If a law enforcement officer failed to adhere to certain regulations, any subsequent evidence that has been acquired with that machine may be inadmissible in court.
Our team will challenge any evidence against you that we believe is unfair! In doing so, we will be able to ensure that your rights are upheld and that you receive a fair criminal trial.
What If I Refuse to Take the Test?
In California, all drivers are subjected to "implied consent laws." This means that anyone who has obtained a valid driver's license in the state has knowingly agreed to submit to chemical testing at a law enforcement officer's request—which includes breath, urine, and blood testing. Failing to comply could have steep ramifications, including fines, jail time and the suspension of one's license. Additionally, law enforcement can still make an arrest without acquiring this type of evidence, as well as use your refusal as proof of your guilt in a subsequent criminal trial.
Need Legal Help? Contact Our San Diego DUI Lawyer for Support
Whether it is a first offense, second offense or you have received multiple DUI charges in the past, the laws concerning your blood alcohol concentration level will always be put into effect if you have been suspected of drinking and driving. Depending on the number of offenses and the circumstances of your case, you could be charged with a misdemeanor or a felony, and either conviction could stand to greatly affect your future lifestyle and rights. No one wants to face these types of consequences, which is why it is imperative to take immediate action after an arrest for drunk driving. At jD Law Criminal Defense Attorneys, our San Diego criminal defense lawyer is board certified in criminal law and is a former police detective, giving him a serious advantage in and out of the courtroom. To get started, simply call our office at (760) 630-2000 and schedule a confidential consultation or fill out a free case evaluation online.
Sample of Case Results
- DUI with BAC of .23% -
Charges Reduced - DUI With BAC .17 -
Reduced to Wet Reckless - Felony DUI With Collision With BAC .18 -
Charges Reduced
View more case results here.
Further Reading
Why Is California’s BAC Limit for DUIs 0.08?
Beating a DUI With a Blood-Split Motion
Alcohol in the Blood: Understanding BAC Levels in California
Can I Legally Refuse a Breathalyzer Test?
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