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How Accurate Is A Breath Test In A NC DWI Case?


If you have been arrested for DWI in North Carolina, you already know that state law requires you to submit to a chemical analysis to determine your blood alcohol content (BAC). The most common chemical analysis is a breath test. In North Carolina, law enforcement agencies use a breathalyzer, also known as an intoximeter, to measure your BAC. If your BAC is over the legal limit of 0.08, this can be used as evidence in court to convict you of driving while impaired.

Are the Machines Used for Breath Tests Accurate?

The Intox EC/IR II is the machine used in North Carolina for breath tests. This is not the same type of machine as the portable breath test (PBT) used at a DWI stop to support probable cause for an arrest. You can refuse to take a portable breath test; however, once you are arrested on an NC DWI charge, you must submit to a breathalyzer test when you arrive at the police station. If you refuse to take the breath test, your driver’s license will be revoked for one year. Because most people need their driver’s license, they submit to the breath test. Unfortunately, these breath tests are not always 100% accurate.

There are several reasons why a breath test may give inaccurate readings. While most people assume that breath tests are accurate, breathalyzers are machines and machines can fail. In addition, the person operating the machine can make mistakes that will cause the results to be inaccurate. A breath test measures the amount of alcohol in your breath and uses this information to calculate your BAC level at the time you were arrested for DWI. Retrograde extrapolation is used to calculate your BAC level at the time you were pulled over.

This method of calculating a person’s BAC level at the time of the DWI arrest does not take into consideration that each person’s body metabolizes alcohol differently due to the weight, age, and health of the individual. Unfortunately, courts accept the results of a breath test as evidence at a trial. Physical conditions such as acid reflux and some types of dental work can also cause false readings on a breath test but these elements are not always taken into consideration by law enforcement officers.

Can I Fight a Breath Test?

The attorneys of Welch and Harris, LLP are familiar with the inconsistencies and problems of breath tests. They have the experience and knowledge needed to challenge breath test results. If you have failed a breath test, this does not mean that you will be convicted of DWI. Never assume that a breath test is 100% accurate. Contact our office to schedule a consultation to discuss your legal options for fighting an NC DWI charge.

Contact an Experienced Jacksonville DWI Attorney

“Attorneys Who Aggressively Protect Your Rights”

Welch and Harris, LLP is a full-service Jacksonville Criminal and Civil law firm that is committed to providing results-driven legal representation to businesses and individuals seeking an alternative to large-firm representation. We focus on getting you the results you want while offering you a cost-effective solution to your legal needs. We understand that we work for our clients; therefore; our attorneys communicate regularly with each client to ensure that the client knows what is going on with the case.

When you have legal problems, you need an experienced legal professional in your corner. No matter the case, you should have an attorney working for you who knows the law and who has the experience to get results. We represent clients throughout Duplin County, Onslow County and the surrounding communities. Call our office at (910) 405-8459 or contact us online today for a free case evaluation.