What is the purpose of standardized field sobriety tests (SFSTs)?

• A. To determine vehicle ownership.
• B. To assess impairment through standardized roadside tests indicating potential alcohol or drug impairment.
• C. To measure speed.
• D. To inspect the vehicle's mechanical condition.

Answer: (B)

SFSTs are designed to assess impairment through standardized roadside tests that indicate potential alcohol or drug impairment. By following uniform procedures and scoring, officers can detect cues in balance, coordination, and cognitive-motor ability that suggest intoxication. The common tests—such as a walk-and-turn, a stand-and-deliver, and horizontal gaze nystagmus—are used because their standardized format helps reduce variation in how they’re performed and interpreted, making it more likely to identify real impairment in a roadside setting. These tests help establish probable cause for arrest and guide whether further chemical testing is appropriate to measure the level of impairment. They’re not about vehicle ownership, speed, or inspecting the vehicle’s condition, which are unrelated to impairment. Keep in mind they’re not perfect—factors like injuries, fatigue, medications, or environmental conditions can affect performance, and the results don’t provide an exact blood alcohol concentration.