RI Field Sobriety Tests

NHTSA's own research claims 88% accuracy for HGN, 79% for WAT, and 83% for OLS - when administered exactly to protocol. Real-world accuracy is substantially lower because of administration deviations, environmental factors, and driver-specific medical conditions.

HGN is the Horizontal Gaze Nystagmus test, the first NHTSA standardized field sobriety test. The officer holds a stimulus about 12-15 inches from the driver's face and moves it slowly side to side, watching for involuntary eye jerking (nystagmus). The officer scores 6 possible clues. NHTSA studies claim 88% accuracy when administered properly, but the test is highly vulnerable to administration errors and medical false positives.

There is no separate statutory penalty. The officer will likely use your refusal as part of their probable cause for arrest, and the case will proceed based on observed driving, smell of alcohol, admission of drinking, and any other indicators. Refusal is not the same as the chemical test refusal at the station, which carries license suspension penalties under § 31-27-2.1.

Many. Inner ear disorders and vertigo affect HGN, WAT, and OLS. Lower back, hip, knee, and ankle injuries affect WAT and OLS. Age over 65 and weight over 50 lbs above ideal affect WAT and OLS per NHTSA's own protocols. Diabetic neuropathy affects balance. Certain medications cause natural nystagmus. Head injury history affects HGN. Anxiety affects all three. Documenting these conditions matters.

Yes. FST evidence is regularly challenged on grounds including improper administration, deviation from NHTSA protocol, environmental factors (uneven roadway, lighting, weather), driver-specific issues (age, weight, medical conditions, injuries), officer training and certification status, and inconsistencies between recorded clues and dash cam or body cam evidence.

No. Field sobriety tests in Rhode Island are voluntary. Unlike the chemical test (which carries license suspension under § 31-27-2.1 if refused) or the preliminary breath test (which carries a small infraction under § 31-27-2.3 if refused), there is no separate statutory penalty for refusing FSTs. The officer can use the refusal as part of their probable cause assessment, but no specific penalty attaches to the refusal itself.

The three NHTSA-standardized field sobriety tests used in Rhode Island are: (1) Horizontal Gaze Nystagmus (HGN), an eye-movement test; (2) Walk-and-Turn (WAT), a heel-to-toe walking test; and (3) One-Leg Stand (OLS), a 30-second single-leg balance test. Officers may also administer non-standardized tests like reciting the alphabet or counting backwards, but those are not NHTSA-validated.