what are clues in field sobriety tests
Standardized Field Sobriety Test. Definition: The Standardized Field Sobriety Test (SFST) is a battery of 3 tests performed during a traffic stop in order to determine if a driver is impaired. The 3 tests that make up the SFST are the horizontal gaze nystagmus (HGN), the walk-and-turn, and the one-leg stand tests.