A breathalyzer machine is designed to measure ALCOHOL. If the beer has no alcohol content, and the breathalyzer test is positive, then the alcohol is coming from another source, either internal or external.
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Dan J. Weisenburger
Attorney at Law
A 'breathalyzer' is a brand name for an alcohol detecting instrument. If I understand your question, you are asking whether non-alcoholic beer will register on an alcohol detecting instrument. Michigan employs Datamasters (stationary devices found in the police station) used for the collection of court-admissible evidence of bodily alcohol presence. A PBT instrument (portable device) detects evidence of bodily alcohol presence but is not admissible in court for that particular purpose. It is an investigation tool designed to raise probable cause. AS to the detectibility of 'non-alcoholic' beer, it depends on how much you have in your system and how much alcohol is found in the beverage. All beer has some alcohol though 'non-alcoholic' beer has only slight quantities. The short answer to your question would be 'maybe' depending on the device used and how much non-alcoholic beer you have had to drink.
Some NA beer has trace amounts of alcohol in it despite the advertising. Be careful. It could register. At the very least, you will smell like alcoholic beverages to the officer because of the way the drink reacts in your mouth.