Sean P. Quinlan, Esq. monogramSean P. Quinlan, Esq.Pennsylvania Defense Attorney
Video Library · Pennsylvania DUI Defense

DUI Field Sobriety Tests: What Police Don't Tell You (Pennsylvania DUI Attorney Explains)

Pennsylvania DUI field sobriety tests are voluntary and often administered incorrectly. Learn what officers don't tell you and how body-cam footage can win a case.

← Back to all videos
Summary: The three standardized field sobriety tests — horizontal gaze nystagmus, walk-and-turn, and one-leg stand — are voluntary in Pennsylvania. Most people fail them even when sober because poor surfaces, medical conditions, nervousness, and unclear instructions all mimic impairment cues. In this video, attorney Sean Quinlan explains what police do not always tell drivers, how the NHTSA manual requires each test to be administered, and why body-camera footage is often the best defense evidence. He covers the exact mistakes officers make during demonstrations, counting, and scoring, and how those deviations become suppression and reasonable-doubt arguments at trial.

Why this matters for your Pennsylvania DUI case

Field sobriety tests are the bridge between the traffic stop and the arrest. If the officer administered them incorrectly, the probable cause for the arrest can collapse — and the breath or blood evidence that followed can be suppressed.

Key takeaways from the video
  • Field sobriety tests are voluntary; you cannot be forced to perform them.
  • The tests only have scientific value when the officer follows the NHTSA manual exactly.
  • Wrong surface, lighting, footwear, or instructions can invalidate the results.
  • Body-camera footage often shows discrepancies the officer's report does not mention.
  • A flawed test can undermine probable cause and lead to suppression of later evidence.
Related resources

Free Consultation

The sooner we talk, the more we can do.

Every hour matters in a DUI or criminal case. Call directly and speak with Attorney Quinlan — not an intake desk.

(717) 724-7503 Schedule a consultation

This video and page are general legal information about Pennsylvania DUI defense and do not constitute legal advice for your specific case. Every case turns on its own facts. Contact a licensed Pennsylvania DUI attorney to evaluate your situation.

Call Text Book