Know Your Blood Alcohol Concentration FAQs

In Massachusetts, if you are stopped by police on suspicion of operating under the influence (OUI), there’s a good chance that you will be asked to submit to a breath test. This test measures the concentration of alcohol in your blood, also known as your BAC. You can refuse to take the test, but there are consequences for doing so. Namely, you will face an automatic, six-month license suspension. That being said, a reading above 0.08 percent will likely carry an even stiffer penalty.

Most folks have heard of a breathalyzer test, and know that a BAC below 0.08 percent is the legal limit in MA. But notably fewer understand the different methods used to measure BAC, their accuracy, and how to challenge results in court. The FAQs below provide answers to all of those questions, and more. A Boston OUI defense attorney can help you determine how to proceed if you have been charged with OUI.

How is BAC Measured?

Although the breathalyzer (breath test) is the most commonly used method for measuring BAC, it is far from the only one. In fact, a total of five bodily samples can be screened for BAC. These are breath, blood, hair, saliva, and urine. Having someone blow into a tube is much less invasive than, say, collecting urine or blood samples. As a result, breath tests are far more likely to be used by law enforcement during an OUI stop. Although saliva tests can be administered in an equally non-invasive manner, they are less common than breath tests. This is likely due to the ease of administering a breath test, and the fact that it doesn’t require the handling of bodily fluids (saliva).

How Does a Breathalyzer Work?

There are various types of breathalyzer machines. While some use the “wet chemical” technique to measure BAC, the most common technique, infrared spectroscopic analysis, measures the content of alcohol in exhaled vapors. These vapors absorb light waves of a specific frequency based on the concentration of alcohol. A computer, in turn, translates this information into a BAC measurement.

Can You Trick a Breath Test?

If you are actually intoxicated, none of the myriad “tricks” circulating out there can help you beat the test. Regardless of how many breath mints or onions you eat, or if you hide a penny under your tongue, the breath test will know if you are drunk. Some rumored methods of beating the test, such as gurgling with mouthwash, can actually raise your BAC.

Are Breath Tests Always Accurate?

Definitely not. However, breathalyzer results are widely accepted as accurate by law enforcement and most courts. The reality is, breathalyzer readings can be off by up to 15 percent when compared to a more accurate blood draw. Courts have thrown out plenty of breath test results since their inception, but fighting an over-the-limit reading requires the assistance of an experienced, and highly-skilled MA OUI defense attorney.

Can I Fight My Test Results in Court?

Of course you can. There are multiple regulations surrounding the use and maintenance of breath tests. A skilled lawyer can analyze the details of your arrest, and the device’s maintenance records, to determine if all regulations were followed to a T. Readings can vary based on the device’s temperature, the individual’s body temperature, the presence of hematocrit in the blood, poor device maintenance, and an improperly calibrated device.

Altman & Altman, LLP—Boston’s Premier OUI Defense Law Firm

If you have been charged with OUI, the skilled legal team at Altman & Altman, LLP can help. We have been protecting the rights of individuals charged with crimes for more than 50 years. Our experienced, knowledgeable attorneys have an impressive track record of getting clients’ charges reduced, or dismissed entirely. Don’t go through this difficult time alone, we can help. Contact Altman & Altman, LLP today for a free and confidential consultation about your case.

Contact Information