The DUI Breath Test
The breath test is the most common way for law enforcement to determine a person’s blood-alcohol concentration, or “BAC”. Although the breath-testing device seems to have taken on an aura of scientific certainty, it is really subject to a host of accuracy problems and a breath-test result can often be wholly discredited by a skilled DUI attorney. Inaccurate breath-test results may be the leading cause of wrongful arrests and convictions of people who are really below the legal limit.
Successful challenges to the breath-test
Fifteen-minute observation period
Before a police officer can give you a breath-test he is supposed to watch you continuously for 15 minutes before the test to make sure that you do not belch or regurgitate. Even the slightest belch could bring alcohol to your mouth and give a false high reading on the breath test. This 15-minute observation period is required by law in order to ensure that the breath test reading is reliable.
Despite the legal requirement of a continuous 15-minute observation period, law enforcement officers commonly fail to perform it. Often, the officer will not continuously observe the subject but will do paperwork or perform some other function when he is supposed to be paying attention to the person about to take the test. If the continuous observation is not performed as directed by Title 17 of the California Code of Regulations, then the result is not reliable. An experienced DUI lawyer will be able to expose the officer’s error and undermine the validity of the breath test.
Inherent error of the Machine
Breath-testing devices all have an inherent error of plus or minus .02%.
This means that a true blood-alcohol of .06% could give a false reading
as low as .04% or as high as .08%. Thus, if your reading was close to the
legal limit, the inherent error of the machine could make all the difference.
Machine not calibrated or maintained properly
The breath-testing machines are sensitive electrical devices that require regular maintenance and calibration. That’s why California law requires that a breath-testing device be regularly calibrated in order for the test results to be valid. The calibration and maintenance of these devices must be documented and these documents should be subpoenaed by your DUI lawyer. If the machine was not properly calibrated or maintained in accordance with Title 17, then the results are unreliable and your DUI lawyer should bring a motion to have the results suppressed or excluded.
A breath test is supposed to measure the alcohol from air deep in your lungs. However, if even a tiny trace of alcohol is in your mouth, this could easily cause a false high reading on the breath test. Mouth alcohol can come from several sources including alcohol in food particles trapped in dental work, Gastro Esophageal Reflux Disease (GERD) or Acid Reflux, alcohol-based medications and mouthwashes. If you suffer from GERD or Acid Reflux be sure to tell your Orange County DUI lawyer.
The breath test is always given after the time of driving. Therefore, a breath test result does not tell us what your BAC was at the time of driving. This is important because your BAC is always changing. When you driving alcohol, it takes anywhere from 20 minutes to three hours for all of the alcohol to move from your stomach to your blood.
Example: You consume three beers and some food and then drive home. Some of the alcohol you drank is still be in your stomach. At the time of driving your BAC is a .06%. You are stopped and the officer does a DUI investigation. 30 minutes after the stop you take the first breath test. Now, all of the alcohol that was in your stomach when you were driving has moved to your blood. Now, your BAC is a .09%.
In this example, the breath test showed what your BAC was when you were on the side of the road but it doesn’t show what your BAC was when you were driving. It is not against the law to have a BAC of .09% on the side of the road. It is only against the law to have a BAC of .09% at the time of driving. An experienced DUI attorney can present your Rising defense to get your case reduced or dismissed. The success of the Rising defense often depends on your statements to the police about when you drank, how much you drank, and what you ate as well as how close your BAC is to the legal limit.
Test outside 3-hour presumption
There is a legal presumption that a blood or breath test within three hours of driving is valid. However, if the test was given beyond the three-your period, there is no presumption of validity.
Diet or Diabetes
A high-protein, low-carbohydrate diet can also cause a false high reading on a breath test. This type of diet will cause the body to manufacture ketones which, in turn, produce isopropyl alcohol in the body. A breath-testing device will not be able to distinguish the isopropyl alcohol form ethyl alcohol (the alcohol we drink) thus producing a false high reading on a breath test.
Likewise, diabetes can have the same effect, causing the body to create ketones and isopropyl alcohol. Therefore, if you have diabetes or were on a high-protein, low-carbohydrate diet at the time you were arrested, it is very important to tell your Orange County DUI attorney.
If you would like to speak to a veteran Orange County DUI lawyer about possible defense in your case, call The Law Office of EJ Stopyro at (949) 559-5500. We are located at 32072 Camino Capistrano, 2nd floor, San Juan Capistrano, CA 92675. We also have meeting offices available throughout the county.