Gastroesophageal Reflux Disease (GERD), acid reflux, and heartburn are all recognized medical conditions that, if active during a DUI investigation, could negatively affect your BAC level. If you experience any of these conditions just prior to or during a DUI breath test, the breath testing instrument may report a falsely high BAC.
The instrument may, for example, report a BAC level of .12 for an individual whose true BAC at the time is a .06.
Even if you don't suffer from chronic GERD, simply eating a spicy meal, a greasy meal, or a very large meal may cause a temporary acid reflux that fools the breath test.
All too often, this leads to innocent people being wrongly arrested and wrongly prosecuted for driving under the influence.
The technology behind California breath testing instruments
California DUI breath testing is designed to measure the amount of alcohol in one's deep lung tissue, otherwise known as "alveolar air". The amount of alcohol in the deep lung air is thought to correlate to the amount of alcohol in the bloodstream.
GERD, acid reflux, and heartburn cause undigested or semi-digested stomach acids (containing alcohol) to travel from your stomach back up to your mouth and throat. (See Figure A). This creates a defect in DUI breath testing known as "mouth alcohol." Mouth alcohol exists at a much higher concentration than alcohol in the deep lung tissue.
When stomach acid enters the mouth or throat...either because you chronically suffer from GERD, acid reflux, or heartburn...or because you ate a greasy or spicy meal...the DUI breath testing instrument measures mouth alcohol instead of the more reliable deep lung air.
This almost always results in an inaccurate and falsely high reading.
A good California DUI defense attorney and his/her DUI expert witness will explain this concept to the judge and jury.
Regurgitation can cause a false high reading on California DUI breath testing instruments
California's DUI laws set forth a number of regulations in an effort to secure accurate DUI breath test results. One of these safeguards is that the officer must observe you for at least fifteen minutes prior to your breath test.1
This "observation period" is designed to ensure that you don't eat, drink, smoke, vomit, or regurgitate just prior to your test...all acts that could adversely affect the accuracy of your breath test results.
The arresting officer will most likely testify that he/she properly observed you in accordance with this California DUI law. However, as the Victorville CA DUI attorney Michael Scafiddi explains2, "Even assuming this is true, regurgitation caused by GERD, acid reflux, and/or heartburn isn't necessarily apparent to an onlooker."
As a result, even though the officer may honestly believe that you didn't burp, belch, or regurgitate while he/she observed you, the officer may have simply been unaware that you did.
This is because regurgitation is a constant flow of gases that flow to and emit from the stomach.3 Because it is constant, it may be visually undetectable to an observer. So while we typically think of regurgitation as synonymous with an obvious attempt to vomit, that's not always the case.
Using GERD, acid reflux, or heartburn to defend your DUI case
Your doctor can perform tests to determine if you suffer from one of these conditions. This information can be extremely useful as an aid in your California DUI defense. It can also be important to your health. GERD is an under-diagnosed condition that, if left untreated, can lead to esophageal erosion and even stomach cancer.
And the fact is that even if you don't have a chronic and regular reflux condition, it still occurs periodically in a large portion of the population. This means that your DUI defense lawyer could raise acid reflux as a possible DUI defense even if you don't regularly suffer from this condition.4
If you have additional questions or would like to confidentially discuss your case with one of our California DUI defense attorneys, please don't hesitate to contact us. We have local DUI law offices in the San Francisco Bay area, San Jose, Ventura, Los Angeles, Orange County, San Bernardino, Riverside, and several surrounding areas.
You may also find helpful information in our related articles on Mouth Alcohol and its effects on your BAC, California Breath Testing, Vehicle Code 23152b Driving with a BAC of 0.08%, and California DUI defenses.
1California's DUI laws, per Title 17 of the California Code of Regulations, require than an officer observe a DUI suspect for 15 continuous minutes prior to conducting a DUI breath test. This 15-minute observation period is critical. Contact us for more information about how the failure to follow this requirement can aid your case.
2Victorville CA DUI attorney Michael Scafiddi is a former DUI enforcement officer who has nearly a quarter century of combined experience dealing with DUIs. He uses that experience today to defend clients accused of DUI throughout the high desert, including Victorville, Barstow, Baker, Hesperia, Apple Valley and Adelanto.
3Stedman's Medical Dictionary -- (Regurgitation is "the return of gas or small amounts of food from the stomach".)
4MedicineNet.com -- What is GERD (acid reflux)? ("In fact, the reflux of the stomach's liquid contents into the esophagus occurs in most normal individuals. One study found that reflux occurs as frequently in normal individuals as in patients with GERD.")