What is the purpose of field sobriety tests?

• A. To assess whether impairment affects a driver’s ability to operate a vehicle safely and to establish probable cause for chemical testing.
• B. To determine legal guilt in a DUI case.
• C. To measure blood alcohol concentration directly at the scene.
• D. To evaluate driving skill without linking to impairment.

Answer: (A)

Field sobriety tests are used to determine if impairment is affecting a driver’s ability to operate a vehicle safely and to establish probable cause for requesting a chemical test. They act as performance indicators that help an officer decide whether to detain or arrest and to justify asking for a breath or blood test, which can then measure alcohol or drug levels. The tests themselves do not directly measure blood alcohol concentration at the scene, and they are not a determination of legal guilt—that decision comes later in court after all evidence is reviewed.