Although licensed to practice law in CA only, your question is not a legal question but rather more of a scientific one.
To answer your question, yes, acide refulx or vomiting does affect the breath test reading. Simply put, the breath test is suppose to test for expired air in the lungs, when you vomit, there is mouth alcohol present which often produces higher results on the breath test.
Set an appointment and go see a local criminal defense attorney who can explain this in a lot more depth to you.
You should speak with a specialized DUI attorney in your area, preferably one who is a member of the National College for DUI Defense. There may be administrative or other regulations that require a certain waiting period prior to administering a breath test under the circumstances. If these procedures were not followed, and the test result obtained too early, it may affect the admissibility of the chemical test result at trial. You may also want to speak with your attorney about whether GERD, a diagnosed medical condition involving acid reflux, could also be present and what affect that would have on the test.
In Michigan, there's an administrative rule called the "15 Minute Observation Rule" which the datamaster operator must follow. During that 15 minute observation, the police officer must ensure that you are not about to regurgitate/vomit prior to administering the BAC test otherwise the results can be erroneous and the Judge can render the BAC results inadmissable.
Daniel Hajji & Associates
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