When a motorist in Pensacola is pulled over on suspicion of drunk driving, in addition to a chemical test, police may also ask the motorist to perform a field sobriety test. However, not all field sobriety tests are equal, and the National Highway Traffic Safety Administration only recognizes three standard field sobriety tests.

The horizontal gaze nystagmus test

Even when we are sober, our eyes naturally “jerk” when we look from one side to the other. If you are under the influence of alcohol, this jerking is exaggerated. Police will test for this jerking by having you follow their finger or a light as it moves side to side, making observations of your gaze during this process. However, according to the NHTSA, the horizontal gaze nystagmus test only accurately identifies drunk drivers with a blood alcohol concentration of 0.10 or higher 77% of the time.

The walk-and-turn test

In this test, the police will ask you to walk nine steps in a row heel-to-toe, and then turn around on one foot and walk back the same way. Police will look for signs of impairment such as staggering, starting to walk before the officer finishes giving instructions or losing balance, among other indicators of impairment. However, the NHTSA reports that the walk-and-turn test only accurately identifies drunk drivers with a BAC of 0.10 or higher 68% of the time.

The one-leg stand test

In this test, the police will have you stand with one foot six inches in the air and then count starting at 1,001. Police will look for signs of impairment such as hopping, swaying, or putting your foot down, among other indicators of impairment. However, the NHTSA reports that the one-leg stand test only accurately identifies drunk drivers with a BAC of 0.10 or higher 65% of the time.

Field sobriety tests are not infallible

As this shows, while field sobriety tests are commonly used by police, they are not always accurate. A sober person could fail these tests if they are nervous or under pressure, or if they have a medical condition that makes these tests difficult to perform. Those in Pensacola who are charged with drunk driving based on a failed field sobriety test will want to seek the help needed to develop a solid defense strategy.