Challenging Field Sobriety Tests in North Carolina

challenging field sobriety tests

If you were pulled over and a police officer suspects you were driving while impaired, you may be asked to perform Field Sobriety Tests (FSTs). These tests are commonly used by law enforcement officers to assess whether a driver is under the influence of alcohol. Challenging field sobriety tests in the moment--or after it has already been performed--may feel like a bad option, but it is good to know what your options are.

If you are facing North Carolina DWI charges, it is important that you understand the FSTs you were asked to perform, the limits of their effectiveness in proving someone was under the influence of alcohol, and how an experienced criminal defense lawyer can challenge field sobriety tests before and during trial.

Understand Field Sobriety Tests in North Carolina

In North Carolina, police may use a combination of standardized and non-standardized field sobriety tests. While police officers in North Carolina technically cannot use non-standardized FSTs to formulate an opinion on whether a driver is under the influence, many officers use them anyway.

Police officers are trained to look for certain “clues” that allegedly indicate that a driver is under the influence of alcohol. These “clues” include lack of focus, poor coordination, and difficulty completing the tasks.

The officer will evaluate the driver on how well they performed the FSTs. It is important to note, however, that a driver does not pass or fail the FSTs. Instead, the officer evaluates how well the driver performed the tasks and, at trial, will testify that the driver “did not perform the tasks as demonstrated and instructed.”

Standardized Field Sobriety Tests

Standardized field sobriety tests are those that have been approved by the National Highway Transportation Safety Administration (NHTSA). Standardized FSTs include the following three tests that can be used to establish probable cause to arrest a driver for DWI:

  • In the Horizontal Gaze Nystagmus Test, an officer moves a pen or finger in front of the driver’s eyes and observes whether there any delays tracking the movement of the object. If there are delays, this information can be used as an indicator that the driver is under the influence of alcohol. In this test, the officer is looking for alcohol-induced nystagmus. Nystagmus is the involuntary jerking of the eye. It can be caused by reasons other than alcohol as well.
  • Officers may use the One-leg Stand Test (OSL) to assess a driver’s balance and ability to follow instructions.
  • The Walk and Turn Test is also used to assess a driver’s balance and ability to stop and turn on command.

Non-Standardized Field Sobriety Tests

While non-standardized FSTs are not approved in North Carolina, many police officers continue to use them to assess whether a driver is under the influence of alcohol. Common non-standardized FSTs include:

  • The Alphabet Test. The officer will ask you to recite the alphabet.
  • The Finger to Nose Test. The officer asks you to touch one finger to your nose.
  • The Numbers Test. The officer will ask you to count to a number, then count backward from that number.

If you were asked to perform any of these non-standardized tests, a North Carolina DWI attorney can challenge the tests and ask the court to declare them inadmissible at trial.

Attorney Ryan Stowe has received the same NHTSA training that officers receive in both standardized field sobriety testing, as well as advanced level training called Advanced Roadside Impaired Driving Enforcement (ARIDE). This is important for challenging field sobriety tests in North Carolina.

Probable Cause Requirement

To be legally justified in asking a suspect to perform FSTs, the officer must have reasonable suspicion to believe that the driver is impaired. Without reasonable suspicion, there is no cause for further investigation.

To establish reasonable suspicion that a driver is under the influence of alcohol, officers often point to the “odor of alcohol” in the vehicle, red or watery eyes, erratic driving, or slurred speech. But if the police officer cannot articulate a specific reason to believe the driver was under the influence of alcohol, there is no reason for the officer to ask the driver to perform FSTs. A DWI defense lawyer can challenge whether the officer had probable cause to believe you were under the influence of alcohol and, if successful, can have evidence of your performance on the FSTs excluded from trial.

When an officer asks you to perform FSTs, you are under no obligation to do so. However, if you refuse to perform the FSTs, the officer can point to your refusal to perform the FSTs as evidence of your alleged intoxication.

If you do take the field sobriety tests, the officer must administer the tests in strict compliance with the law enforcement procedures and protocol. If the officer does not follow the format for asking a suspect to perform FSTs, a North Carolina DWI attorney can request that the FSTs not be considered at trial. An experienced DUI defense lawyer will request video of a driver’s performance on the FSTs and evaluate the video for strict compliance with law enforcement protocols.

Challenging Field Sobriety Tests in North Carolina

Before asking a suspect to perform field sobriety tests, a police officer should ask whether there are any medical conditions that could affect the driver’s performance. However, many police officers fail to ask, and even if they do, the driver may not be aware of how a medical condition could influence their performance on the FSTs.

Poor performance could be the result of any number of common medical conditions. In many cases, the effects of medication a driver is taking or the driver’s medical condition can be mistaken for alcohol intoxication.

Common medical conditions that can make a driver appear impaired include:

  • Diabetes
  • Drowsiness
  • High blood sugar
  • Low blood sugar
  • Watery eyes due to allergies, exhaustion, etc.
  • General illness
  • Physical injuries such as back pain, knee pain, or balance issues

A skilled DUI defense attorney can also challenge the conditions under which the tests were administered. For example:

  • Was the roadway sloped?
  • Does the officer know how the driver would perform the tests when not under the influence of alcohol?
  • Does the driver generally have poor coordination?

The Stowe Law Firm: Serious Representation for North Carolina DWI Defense

If you have been charged with driving while impaired in North Carolina, the Stowe Law Firm, PLLC can help. With offices in Salisbury, North Carolina, criminal defense attorney Ryan Stowe represents people in Rowan County, Mecklenburg County, Davidson County, Cabarrus County, and Stanly County.

We invite you to learn more about our team and the cases we handle, to get answers to Frequently Asked Questions, and to contact us today to schedule a confidential consultation to discuss your case and how we can help.

Categories: DWI

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Ryan Stowe is the principal attorney at Stowe Law Firm, PLLC. Mr. Stowe is proud to be practicing in his hometown of Salisbury, NC, and is a first generation Rowan County attorney. Mr. Stowe takes pride in being a criminal defense attorney. He focuse…

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