Concord Trial Attorneys

How A BAC Level Is Determined And How To Challenge A BAC Test

When police officers in North Carolina stop a driver for a traffic violation or respond to a car accident, the officer may have a motorist step outside of their vehicle. In matters where drunk driving is suspected, a field sobriety test might be conducted. In order to rule out that a driver is not under the influence of alcohol, certain tests are conducted. In order to establish a driver’s blood alcohol content level, a breath test is often used.

There are several methods to measure BAC. However, these are not always accurate, meaning drivers may have the opportunity in certain circumstances to contest the accuracy and validity of the BAC test. There are five ways to determine BAC. This includes obtaining samples of urine, saliva, hair follicles, blood and breath of a suspect. While there are several methods to establish BAC, the breath test is the only one used broadly by law enforcement because other methods, such as blood, are more invasive.

Breath tests have been considered acceptably accurate when using them as evidence in a criminal charge. However, studies have proven that a breath test reading could vary from the actual BAC level by 15 percent. Thus, some courts throw out this evidence, as reliability is questioned.

Even if a breath test is used to charge an individual with a DUI, it is still possible to challenge the results. A Breathalyzer machine must be routinely tested and calibrated. There are ways to determine if continual and proper maintenance has been carried out on a specific machine. One can also challenge the validity of the test, questioning if there was probable cause and whether all the proper steps have been carried out.

If you are facing drunk driving charge, its important to understand your rights in this matter. Taking the time to construct a defense strategy is your best chance at getting the charges reduced or dismissed.

Source: FindLaw, “BAC Test FAQs,” accessed Jan. 6, 2018