Common Examples of Field Sobriety Tests

Law enforcement officers often use field sobriety tests when they have pulled people over on suspicion of DUI to gauge whether or not the suspect is under the influence of alcohol.

Here are a few common examples of these field sobriety tests and how they’re conducted.

Horizontal gaze nystagmus

This test involves the officer asking the driver to follow a flashlight or pen slowly from side to side by only moving their eyeballs and not their head. The officer will specifically look to see if the eye is unable to follow the object smoothly and if there is a jerking that is clear and distinct when the eye is at maximum deviation. If the driver fails this test, he or she is likely to have a BAC of at least .10. The test is accurate in nearly 80 percent of cases.

One leg stand

In the one leg stand test, the officer will ask the driver to stand on one foot, holding the other foot about six inches off the ground and then count to 30 or until the officer asks the driver to place the raised foot down. The officer will watch for swaying, using arms to balance, putting the foot down before asked, or hopping to keep balance. A failure of the test indicates a BAC of .10 or greater, and the test is considered accurate in about 65 percent of cases.

Walk and turn

In this test, the officer asks the driver to take nine steps forward, heel to toe, in a straight line, then turn on a single foot and walk back. The officer will watch to see if the suspect is able to maintain balance, if the driver stops while walking, if heel to toe is not touched, if arms are used to balance, if an incorrect number of steps is taken or if balance is lost during the turn. Failure of the test has a 68 percent likelihood to indicate a BAC of greater than .10.

For more information about common field sobriety tests, contact experienced Reading, PA criminal defense lawyer David R. Eshelman.