Standardized Field Sobriety Tests During a DUI Stop

 Posted on November 13, 2017 in DUI

Imagine that you have been pulled over on suspicion of driving under the influence, or DUI. The officer approaches your car and asks if you have been drinking. Regardless of your answer, you may be asked to get out of your car and submit to sobriety testing. From you have seen on TV or in the movies, do you know what the test would be? Will the officer ask you to recite the alphabet backwards? Or maybe he or she will have you spell your birth month. While there are many entertaining ways to test a person for potential intoxication, law enforcement officers around the country typically rely on a series of evaluations approved by the National Highway Traffic Safety Administration (NHTSA) known as Standardized Field Sobriety Tests, or SFSTs.

What Are SFSTs?

The SFSTs consist of three separate assessments designed to help an officer estimate a driver’s level of intoxication. These tests can be used in addition to a chemical testing procedure, such as a breathalyzer, or to justify a DUI arrest if such chemical testing provides marginal results or is not available.

Most people have seen or at least heard about each of the three tests comprise the SFSTs, as they have been used regularly of more than four decades. The SFSTs include the:

• Horizontal gaze nystagmus (HGN) test: The subject must follow a slow-moving object—a pen, flashlight, or the officer’s finger—with only his or her eyes. The officer is looking for involuntary jerking of the eyeball, called nystagmus, which may be exaggerated by intoxication.
• Walk-and-turn test: The subject must walk nine steps, heel to toe, on a marked or imaginary straight line, turn 180 degrees and walk nine steps back. The officer is looking for signs of impairment such as poor balance, trouble counting, and more.
• One-leg stand test: The subject must stand on one foot, holding the other foot about six inches off the ground and counting aloud for approximately 30 seconds. The officer is, again, looking for trouble balancing, trouble counting, and other signs of being impaired.

Challenges to the SFSTs

There are several grounds on which to dispute an officer’s conclusions from field sobriety tests, including preexisting physical conditions that can affect the same factors the tests are designed to observe. For example, a person suffering from inner-ear problems and vertigo may have difficulty balancing while completely sober. Therefore, the walk-and-turn and the one-leg stand would not likely be good indicators of that person’s intoxication level. Current estimates place the accuracy of the SFST around 90 percent when conducted properly. This means that about one out of every ten tests could conclude that a driver is intoxicated when he or she is not. If the tests are not conducted properly, the result may be even more suspect.

If you have been arrested and charged with DUI based on the results of field sobriety tests, contact an experienced Rolling Meadows DUI defense attorney. We are equipped to help you challenge the testing procedures and results, as well as any other detail of your arrest. Call Cosley Law Office at 847-253-3100 for a free consultation today.

Sources:

http://duijusticelink.aaa.com/issues/detection/standard-field-sobriety-test-sfst-and-admissibility