Field sobriety tests are used for what purpose?

• A. To punish drivers.
• B. To determine blood alcohol content directly.
• C. To assess impairment independent of other evidence.
• D. To assess impairment and help establish probable cause for arrest.

Answer: (D)

Field sobriety tests are used to assess whether a driver is impaired and to provide evidence that supports probable cause for an arrest. These in-field tasks are designed to reveal observable signs of impairment through performance deficits and physical cues, which, when combined with the officer’s observations of driving behavior and other signals (like slurred speech or odor of alcohol), help determine if there is enough grounds to arrest and pursue further testing. They do not directly measure how much alcohol is in the bloodstream—that requires a chemical test such as a breath or blood test. The tests are a diagnostic step, not a punishment, and they contribute to establishing probable cause for subsequent actions.