Straightforward, Diligent Representation You Can Count On
Call Today For A Free Consultation

Call 704-868-3434

How Accurate Is a Breath Test in a North Carolina DWI Case? 2024

On Behalf of The Law Firm of Brent D. Ratchford |

When facing a DWI charge in North Carolina, a crucial piece of evidence often used against drivers is the result of a breathalyzer test. This test measures a person’s blood alcohol concentration (BAC) to determine whether they are over the legal limit; however, breath tests are not always dependable. So, just how accurate is a breath test in a North Carolina DWI case? A Cherryville, NC DWI lawyer can help examine the circumstances under which the breathalyzer was administered and challenge its validity if necessary.

Various factors can affect the accuracy of a breath test, but the good news is that those results can be challenged in court.

breath test in a north carolina dwi case

What Is the Margin of Error on a Breathalyzer Test?

Breathalyzer tests have a known margin of error, which can skew the results of an individual’s BAC. Given this potential margin of error, it is possible that a person’s BAC may not have truly exceeded the legal limit of 0.08% at the time of driving, especially if their reading is borderline.

How Often Are Breathalyzers Wrong?

Breathalyzers can be wrong more often than many people think due to several factors that affect their accuracy. There are several ways in which a breathalyzer can provide incorrect results:

  • Improper Use: There are specific protocols that law enforcement officers must follow when administering a breath test. Failure to do so can lead to inaccurate results.
  • Device Malfunction: Like any other technology, breathalyzers can malfunction, leading to false readings. A faulty machine can misreport the BAC, giving readings that are higher or lower than the true level.
  • Health Conditions: Individuals with medical conditions like GERD (Gastroesophageal Reflux Disease) or diabetes can produce false positives on breathalyzer tests. The device may read alcohol vapors from the stomach or other substances, such as acetone, in the breath, mistaking them for ethanol.

Because of these factors, breathalyzer tests can sometimes give readings that are not reflective of a person’s actual BAC, leading to inaccurate charges of driving while impaired.

Challenging Breathalyzer Results

It is possible to successfully challenge breathalyzer results in court; however, it does require a strong defense strategy and a thorough investigation into the specific circumstances of the test. Here are some of the ways breathalyzer results can be challenged in court:

  • Improper Calibration or Maintenance: Defense attorneys can request maintenance records of the breathalyzer used during the arrest. If the device was not calibrated correctly or was overdue for maintenance, this can cast doubt on the reliability of the results.
  • Failure to Follow Proper Protocol: Law enforcement must follow strict procedures when conducting a breath test. For example, officers are required to observe the individual for at least 15 minutes before administering the test. If this protocol is not followed, the results may be challenged.
  • Health and Medical Conditions: Defendants with medical conditions that can interfere with breathalyzer readings, such as diabetes or acid reflux, can use this as a defense. A defense attorney might call on medical professionals to testify that the individual’s condition could have skewed the test results.
  • Mouth Alcohol Contamination: Breathalyzers are designed to measure alcohol from deep lung air, but alcohol from the mouth, known as mouth alcohol, can lead to falsely elevated readings. This can occur if a person burps, vomits, or recently used mouthwash before the test. Defense attorneys can argue that mouth alcohol contamination may have affected the results.
  • Test Timing: BAC levels can fluctuate, and there may be a significant difference between a person’s BAC at the time of driving and when the breath test was administered. This is known as the rising BAC defense. If the driver had consumed alcohol shortly before driving, their BAC could have been under the legal limit while driving but then risen by the time the test was taken.

FAQs About Breath Test in a North Carolina DWI Case

Is It Possible That the Breathalyzer Was Broken?

Because a breath test requires regular maintenance and human error can cause maintenance steps to be missed or skipped, it is entirely possible that the breathalyzer was broken at the time that the test was administered. Your DWI defense attorney can investigate all circumstances surrounding the test’s administration and request maintenance records to help build you a solid defense.

Is There Any Recourse If I Blew a High BAC But I Wasn’t Drunk?

Breath tests are generally reliable but not completely foolproof. Factors such as improper calibration, medical conditions, and environmental influences can affect the accuracy of the test, leading to incorrect BAC readings. Additionally, rising BAC could be a damning factor, especially if proper police protocols were not adhered to. Your lawyer can investigate the particulars of the circumstances and build a defense that focuses on the breathalyzer itself.

Are Breathalyzers Typically Wrong?

Breathalyzers may not be as accurate as many believe, but that doesn’t mean they are wrong more often than not. Like all technology, a breathalyzer needs to be in good condition in order to work well. If the device malfunctions or if you suspect it was incorrectly administered, speak to your attorney. If you are able, write down all the events of the traffic stop and provide this information to your attorney as soon as possible.

Can You Successfully Challenge Breathalyzer Results in Court?

Yes, you can successfully challenge breathalyzer results in a North Carolina DWI case. Defense strategies may involve questioning the device’s calibration, the officer’s procedure, or the presence of medical conditions that could have affected the results. It is important that you recount everything you remember about the test to your attorney so that they can begin investigating.

Contact a North Carolina DWI Lawyer

In North Carolina DWI cases, breathalyzer tests are commonly used by law enforcement to measure blood alcohol concentration and determine whether someone is driving under the influence. These tests, while used often, are not without their flaws. With a margin of error, the potential for improper use, device malfunction, and the influence of certain medical conditions, breath tests can sometimes provide inaccurate results.

If you are facing DWI charges and you’re not confident that the breath test was correctly administered, The Law Firm of Brent D. Ratchford is ready to advocate for you and support you as you navigate the legal system. Contact us today to schedule a consultation.

North Carolina DWI Case Resources: