The Tests at the Roadside
ORC 4511.19 — the three standardized tests, and what they are not
Three tests are treated as standardized in Ohio: horizontal gaze nystagmus, the walk and turn, and the one leg stand. The statute lets an officer testify to the results, and the prosecution use them, only where it is shown by clear and convincing evidence that the officer gave the test in substantial compliance with the testing standards in effect at the time, including those set by the National Highway Traffic Safety Administration.
Who handles this in Ohio: Ohio State Bar Association lawyer referral; and legal aid programs and the state offices, listed in the Ohio directory.
- Horizontal gaze nystagmus is the eye test, where the officer moves a stimulus across the field of vision and watches for involuntary jerking.
- The walk and turn is nine heel to toe steps along a line, a turn, and nine back.
- The one leg stand is one foot roughly six inches off the ground while counting aloud.
These are not the chemical test, and implied consent does not reach them. Ohio's implied consent statute is about chemical tests of breath, blood or urine after an arrest. The roadside tests sit before an arrest and are a different thing. The administrative license suspension that attaches to refusing a chemical test does not attach to these, which is the single most confused point on this subject.
What the results are used for is establishing probable cause to arrest, and then as evidence of impairment at trial. Substantial compliance is the standard the statute sets, so how the test was given is itself a question in the case rather than a formality.
- The officer may testify to a roadside test's results, and the prosecution may introduce them, where it is shown that the test was given in substantial compliance with the testing standards then in effect. That has to be shown by clear and convincing evidence, the higher civil burden, and a bare showing that the tests happened is not it.
- Where the results come in, the judge or jury gives them whatever weight it considers appropriate. Admitted is not the same as conclusive.
- Results kept out for want of substantial compliance do not end the probable cause question. The court may still weigh the rest of what the officer saw, such as the driving, the odor and what was said.
- No Ohio statute makes declining the roadside tests a separate offense. Implied consent, and the suspension for refusing, belong to the chemical test after an arrest.
| The question | The roadside tests | The chemical test |
|---|---|---|
| The questionWhen | The roadside testsBefore an arrest, at the roadside | The chemical testAfter an arrest, at the station or a hospital |
| The questionWhat it measures | The roadside testsPerformance the officer observes and scores | The chemical testAlcohol or drug concentration in breath, blood or urine |
| The questionGoverned by | The roadside testsSubstantial compliance with the testing standards | The chemical testThe implied consent statute |
| The questionRefusing carries an administrative suspension | The roadside testsNo | The chemical testYes |
A portable breath device used at the roadside is treated differently from the evidential test taken after an arrest, and Ohio courts have limited what a roadside reading may be used for. That is an argument a lawyer makes on the facts of a case rather than a rule this page can state flatly.
Sources for this section (3)
- ORC 4511.19 — Operating a vehicle under the influence of alcohol or drugs (OVI)
- U.S. Const. amend. IV — Searches and seizures
- ORC 4511.191 — Implied consent to chemical tests
Legal information, not legal advice. Verified as of September 2026. Applying it to a particular situation is the work of a licensed Ohio attorney.