Written by Maya Fouad
When a police officer is conducting a roadside investigation of a suspected drunk driver, a variety of mechanisms are employed as indicators of intoxication. Law enforcement are trained to conduct specific behavioral tests and use certain devices designed to detect levels of intoxication. Officers are often additionally trained to make more general observations of the suspect during roadside investigations of this nature. For instance, the potential odor of alcohol, an individual’s flushed face, or the appearance of the eyes, can all also be additional indicators of intoxication; however, few evidentiary limits apply when an officer with personal knowledge testifies to such observations. In contrast, evidence of intoxication resulting from officers performing more established methods of testing implicate more potential grounds for exclusion.
Since 1981, the National Highway Traffic Safety Admission (NHTSA) of the United States Department of Transportation has produced a series of standardized field sobriety tests which are considered the most effective procedures for testing drivers at roadside for intoxication. The NHSTA’s behavioral test battery has been incorporated into law enforcement training in all states to help police officers in assessing whether a suspected drunk driver is legally impaired. The tests are administered roadside, outside of the car, and after the suspected drunk driver has been identified. The SFST battery is composed of three tests: the Horizontal Gaze Nystagmus (HGN), the Walk-and-Turn (WAT), and the One-Leg Stand (OLS). Since 1995, the Georgia Peace Officer Standards and Training Council has made the three NHSTA-approved field tests the exclusive field tests taught to Georgia officers.