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Can You Challenge the Breathalyzer’s Accuracy?


[Tweet “Unfortunately, the breathalyzer is not an infallible machine.”]

Take note that all states now have per se drunk driving laws which make it a crime for any person with blood alcohol content (BAC) of .08 percent or more to operate a vehicle. In almost all cases, a person’s BAC is what the law enforcement officer’s Breathalyzer’s Accuracy reading says it is. Unfortunately, the breathalyzer is not an infallible machine. It’s flawed, so it should be inadmissible as evidence. For your own protection, you can be prepared for your drunk driving defense because of breathalyzer inaccuracy with the help of an experienced DUI lawyer in Las Vegas.

How breathalyzers work

Breathalyzer attempts to measure a person’s BAC through a sample of his breath using a pre-set conversion formula. It assumes that a specific ratio between blood alcohol content and breath alcohol content of 2100:1 is applicable for every person. You see, for an average person, it has been determined that 1 part of alcohol found in the breath translates to 2100 parts alcohol in the blood. But what if you are not an average person? Unavoidably, there will be a problem with the breathalyzer accuracy.

The 2100:1 partition ratio is based on the height, weight and overall health of an average person. If your biometrics differs significantly from the norm, then the breathalyzer reading will not accurately reflect your actual BAC. If you are too tall or too short or too old or too sickly or you are in other ways not physically average, then the 2100:1 partition ratio may not be applicable for you. In which case, the alcohol content of your blood may not necessarily be what the breathalyzer machine says it is.

Breathalyzer accuracy (or lack thereof)

The reliance of the court on the breathalyzer readings as evidence furthermore assumes that the breath sample being analyzed came exclusively from deep within the lungs. This is another serious flaw as the machine cannot distinguish alcohol molecules coming from a person’s lungs from the alcohol molecules coming from that person’s mouth and/or esophagus. Breathalyzer inaccuracy or false BAC readings may result if a person has recently vomited, hiccupped, coughed or burped. Even asthma inhalers, dentures, lip gloss or mouthwash can mislead the breathalyzer in the computation of the BAC based on the sample of the breath introduced.

And that’s not all. A breathalyzer cannot even distinguish alcohol from any other chemical compound that contains the methyl group in its molecular structure. These compounds include acetone which can be detected in the breath of a diabetes patient and other people with lower than normal blood sugar levels. They also include acetaldehyde, which in the lungs of smokers are thirty percent higher than in non-smokers.

Other factors

Then there’s gasoline and toluene found in paint, glue, thinners, cleaning solvents and other industrial compounds which can be inhaled or absorbed through the skin. So if you are a diabetic, or a heavy smoker, or you’ve just been painting your room the whole day, there are chances that you’re BAC reading from the breathalyzer won’t really reflect the actual amount of alcohol in your blood. Chances are you could get a conviction for DUI because of the inherent breathalyzer inaccuracy.

Even more disturbing, police handheld radios and certain types of cell phones can make a breathalyzer give out erroneous or inaccurate BAC readings. The circuitry of breathalyzer equipment can be affected by radio frequency interference or electromagnetic interference being emitted by any electronic device in the vicinity in ways that can cause it to make false test results.

How to fight inaccurate breathalyzer readings

Remember that a breathalyzer test will tend to have a high margin of error. If you have been charged with DUI and/or the per se drunk driving laws, it would be in your best interest to hire an experienced DUI attorney who can help you challenge the reliability and accuracy of the breathalyzer test result that is being used as evidence against you. A good DUI lawyer will know how to prove that your BAC is not what the breathalyzer says it is at the time of testing. Don’t be convicted of DUI because of the problems with the built-in breathalyzer accuracy.

Learn more about breathalyzer accuracy test here.


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