Dayton-Area Appeals Court Tosses HGN Test Results in OVI Case: What State v. Impson Means for You

If an officer had you follow a pen or fingertip with your eyes before an OVI arrest, a new decision from the Dayton-area appeals court is worth knowing about. On October 23, 2026, Ohio's Second District Court of Appeals decided State v. Impson, 2026-Ohio-4182. The court reversed an OVI conviction because the State did not prove the horizontal gaze nystagmus (HGN) test was given the way federal standards require. The court ordered a new trial without those test results.

The Second District hears appeals from Montgomery, Greene, Miami, Darke, Clark and Champaign Counties. Its decisions matter for anyone facing an OVI charge in the Miami Valley.

What Happened in State v. Impson

The case came from the Darke County Municipal Court. According to the opinion, a Greenville police officer stopped Joseph Impson's vehicle at about 2:30 a.m. on February 18, 2025 because its license plate light was not working. The officer reported a strong odor of alcohol, bloodshot and glossy eyes, slurred speech, and an open beer and a bottle of vodka in the vehicle.

The officer gave Mr. Impson the HGN test. He declined the walk-and-turn and one-leg-stand tests. He was charged with OVI under R.C. 4511.19(A)(1)(a), a first-degree misdemeanor, and with a minor misdemeanor for the plate light.

Before trial, his attorney moved to suppress the evidence. The trial court denied the motion, finding the HGN test was "substantially complied with." A jury convicted him of OVI. His sentence included jail time, probation, a $750 fine and a 545-day license suspension.

What the HGN Test Is and How NHTSA Says It Must Be Given

The HGN test is one of the three standardized field sobriety tests in Ohio. As the court described it, the officer holds a stimulus, usually a pen, 12 to 15 inches from the person's face. The officer then watches the eyes for three things:

·       Lack of smooth pursuit: whether the eyes follow the stimulus smoothly.

·       Distinct and sustained nystagmus at maximum deviation: jerking when the eye is moved as far to the side as it will go.

·       Onset of nystagmus prior to 45 degrees.

The National Highway Traffic Safety Administration (NHTSA) manual sets out specific steps, as the opinion explains. When checking smooth pursuit, the officer should make at least two complete passes. The stimulus must move "in a smooth, continuous manner without stopping at either side or the center." When checking for nystagmus at maximum deviation, the officer must hold the stimulus there for a minimum of four seconds. The manual itself says that to "count" this clue, "the nystagmus must be distinct and sustained for a minimum of 4 seconds."

These details matter. Under R.C. 4511.19(D)(4)(b), as the court explained, field sobriety test results are admissible only if the State presents clear and convincing evidence that the officer gave the test in substantial compliance with NHTSA standards.

What the Court Decided

The Second District reviewed the officer's body camera and cruiser camera video. It found that the officer:

·       paused in the center and at each end during the smooth pursuit passes, instead of moving the stimulus continuously, and

·       did not hold the stimulus at maximum deviation for the four-second minimum.

At the suppression hearing, the officer admitted she did not follow proper smooth pursuit procedure and "highly doubted" she reached the required time at maximum deviation. She blamed Mr. Impson for not following directions.

The court acknowledged that Mr. Impson "did not help the situation." But it held that the question is whether the State proved substantial compliance, and "[t]he State did not." The HGN results should have been suppressed. The court reversed the OVI conviction and sent the case back for a new trial at which the State cannot introduce the HGN results.

Why a retrial instead of a dismissal? The court separately found that the trial evidence was legally sufficient to support an OVI conviction. That included the officer's observations, the open containers, the admission to drinking, and his trouble following directions. Officers may also still testify about general observations during the attempted test, such as difficulty following directions. The plate-light conviction was affirmed.

What This Means If You're Facing an OVI in the Dayton Area

1.     Field sobriety tests have rules, and those rules can be enforced. It is not enough for an officer to say a driver showed "clues." The State has to prove the test was given in substantial compliance with NHTSA standards, and the video can show whether it was.

2.     Video is often key. The court relied on body camera and cruiser footage to see exactly how the test was given.

3.     Suppressing one test does not automatically end a case. Other evidence can still support an OVI charge. Each case depends on its own facts.

Attorney Christopher Fogt is certified in NHTSA Standardized Field Sobriety Testing, the same training framework police officers use. He compares how each test was given against the NHTSA manual. Fogt Law represents people charged with OVI in Montgomery, Greene, Miami, Warren and nearby counties. Learn more about our Dayton OVI defense (https://www.fogtlaw.com/ovi-attorney-dayton) and how field sobriety tests work in Ohio (https://www.fogtlaw.com/fst-s-field-sobriety-tests).

Frequently Asked Questions

Do I have to do field sobriety tests in Ohio? Field sobriety tests are generally voluntary. In Impson, the driver took the HGN test but declined the other two. Talk with a lawyer about how this applies to your situation.

What does "substantial compliance" with NHTSA standards mean? Under R.C. 4511.19(D)(4)(b), field sobriety test results are admissible if the State shows by clear and convincing evidence that the officer substantially followed NHTSA standards. Perfection isn't required, but as Impson shows, significant departures can make results inadmissible.

If my HGN test is suppressed, is my OVI case dismissed? Not necessarily. In Impson, the HGN results were excluded, but the court ordered a new trial because other evidence was enough to go to a jury.

Does this ruling apply in Montgomery, Greene and Miami County courts? The Second District hears appeals from those counties (plus Darke, Clark and Champaign), so local trial courts look to its decisions. How it applies depends on each case's facts.

Talk With a Dayton OVI Lawyer

If you've been charged with OVI and the officer used field sobriety tests, the details of how those tests were given may matter. Call Fogt Law at 937-254-2600 to discuss your case.

Source: [State v. Impson, 2026-Ohio-4182 (Ohio App. 2d Dist., Oct. 23, 2026)](https://www.supremecourt.ohio.gov/rod/docs/pdf/2/2026/2026-Ohio-4182.pdf).

This article is general information, not legal advice, and reading it does not create an attorney-client relationship. Every case is different, and prior results do not guarantee a similar outcome.