New Jersey Drunk Driving Defense Update: Cigarette Smoking May Cause Higher BAC Breathalyzer Reading

Many people confronted with a first-time arrest for driving while intoxicated begin to wonder what factors, beyond any actual beer, wine or liquor consumption, affect the blood-alcohol content (BAC) results from an Alcotest or other breathalyzer device. Naturally, as New Jersey DWI defense lawyers, we understand this area of the law quite well. But sadly, the science behind drunken driving arrests and convictions may not always be completely reliable.

Whether a motorist received a breathalyzer test at a mobile DWI unit or at a police department, the machines are very similar. These devices do not measure alcohol content in the blood itself, they are actually designed to detect chemical compounds containing the methyl group of molecules. Based on this methyl measurement, these devices produce a reading (as a percentage of blood-alcohol content) that is used to charge the motorist with driving while under the influence.

One of the weaknesses in this method of BAC measurement is that breathalyzers like the Alcotest machine make an assumption that any methyl molecule detected in a person’s breath is from alcohol. However, methyl molecules are not just found in alcoholic beverages, they exist in other substances.

The fact that the methyl group occurs elsewhere can be important knowledge for one segment of New Jersey’s driving public: Smokers. According to recent studies, breathalyzer machines may have a hard time distinguishing between the methyl molecules in alcohol and those found in acetaldehyde.

For readers who didn’t go to medical school or graduate with a degree in chemistry, acetaldehyde is a compound produced by the liver in small amounts as a by-product in the metabolism of alcohol. What came as a surprise to some researchers is the finding that acetaldehyde concentrations in the lungs of smokers was often many time greater than that found in the lungs of non-smokers.

From this simple finding, it can be deduced that a smoker who is stopped for drunk driving may blow a possibly falsely high BAC reading. To complicate matters, it is also understood that cigarette smoking can affect the body’s absorption of alcohol.

The point here is that a New Jersey motorist and also a smoker could theoretically be charged with drunk driving based on a BAC reading that may have been elevated due partially to additional methyl content due to a smoking habit. Is this enough to fight a DWI arrest in court? Perhaps. And this is why anyone charged with drunk driving should consult a qualified DWI defense attorney to better understand his or her situation. There absolutely no reason anyone should throw in the towel simply because a machine says you were drunk.