Police may pull over a driver under suspicion of drunk driving. During a traffic stop, the police could have the driver do a field sobriety test.
Field sobriety tests are used to determine if a driver is drunk. These test work in the following ways:
1. Horizontal gaze nystagmus test
Under the National Highway Traffic Safety Administration, a horizontal gaze nystagmus test is a kind of standardized field sobriety test. This test involved the driver using only their eyes to focus on an object, such as a finger or pen. The officer will then move the object side-to-side. The intent of this test is to see if the driver has too many involuntary eye movements, which naturally occur but may increase with alcohol or drugs.
2. Walk-and-turn test
Another standardized field sobriety test is a walk-and-turn test. The driver conducting this test will walk nine paces out, toe-to-heal, in a straight line. The driver will then turn and walk back the same way back to where they started. If they have trouble keeping balance, take too many or too few steps or stop too many times, then they may be heavily inebriated.
3. One-legged stand test
The last kind of standardized field sobriety test is a one-legged stand test. The officer may ask the driver to lift one foot slightly off the ground for several seconds. What the officer may look for is if the driver struggles to keep balance, places their foot down before time is over or if they begin hopping to keep balance – each indication that the driver is intoxicated.
4. Non-standardized sobriety test
Law enforcement may ask drivers to perform tests that are considered non-standardized. Non-standardized sobriety tests may have suspected drunk drivers to do various tasks, such as counting backward, reciting the alphabet or touching their nose.
There are times when a driver may not be drunk but fail a field sobriety test. This could happen because a driver has a disability or was fatigued. If this leads to a DUI charge, it may be wise to learn how to create a strong defense.