FIELD SOBRIETY TEST: These are the tests that an officer asks a suspected drunk driver to perform to help him determine if they are under the influence of an intoxicant. These tests are extremely subjective and should not be performed. Examples of FSTs include the HGN, the walk and turn, finger to nose, internal clock, and recounting the alphabet. All FSTs require the person being tested to listen carefully and follow the directions of the officer. Some common mistakes of people not following the directions of the officer include: Not standing in the position the officer describes and remaining in that position until told to move: People tend to start the test before they officer says to start the test. Another example is when the officer tells a suspect to follow the pen with just their eyes, most people will turn their head to follow the pen. These are just a couple of examples. [ return to top of glossary
Field Sobriety Test. Any number of tests used by law enforcement officers, usually on the roadside, to determine whether a driver is impaired. Most FSTs test balance, coordination and the ability of the driver to divide his or her attention among several tasks as once. Other tests, such as the horizontal gaze nystagmus test, are used to measure a subject's impairment level.