The truth behind breath test analyzers: Are they really reliable?

Despite proven inaccuracies, roadside breath test devices are used by law officers in NY to determine whether drivers are drunk.

New York drivers may have been subjected to a roadside breath test at some point in their lives. These tests are often administered by law enforcement officers who pull people over on suspicion of drunk driving. Although hand-held breath test machines are supposed to indicate whether a driver is intoxicated, studies show that the results of these devices may be inaccurate. In fact, the State University of New York at Potsdam reported that breath test results can vary by more than 15 percent when compared to the breath alcohol content level obtained from an actual blood test. Many people are left wondering why officers still use these devices despite their unreliable results, and what is it that makes these machines inaccurate.

A look at the factors that influence breath test readings

Breath test machines are designed to calculate a person's blood alcohol level by evaluating how much alcohol is contained in his or her breath sample. The problem lies in the fact that many breath test devices measure more than just the amount of ethyl alcohol in the driver's breath sample. According to the State University of New York at Potsdam, the following factors can influence a final breath test reading:

• Any residual food, drink, blood or vomit in a person's mouth.

• The presence of cigarette smoke, dirt, gasoline fumes or a number of other pollutants in the air.

• The relative humidity of the environment.

• Whether the machine has been properly calibrated.

• Whether the officer is using the device correctly.

• Electrical interference from cellphones or officers' radios.

Each person has a unique physiological makeup and certain personal variances may cause an exaggerated BAC reading as well.

Breath test studies

In one study, a subject wearing a face mask was asked to spend 20 minutes spray painting a room. Once the task was completed, the subject was given a blood test and a breath test. While the blood test showed that the subject's blood alcohol content level was zero, the breath test results showed a BAC level of 0.075 percent. The legal limit in New York is 0.08 percent, meaning that the subject could have been close to a DWI charge. The subject in this case did not even have any alcohol.

Obtaining help from an attorney

A DWI can wreak havoc on your personal record and could make it difficult for you to receive financial funding, a professional license or even employment in certain industries. A criminal defense attorney in New York may be able to help you explore your legal options and answer any questions you may have regarding your case.