The Ohio State Highway Patrol (OSHP) is now using oral fluid testing to determine drivers’ THC levels. According to a report by NBC4i, OSHP launched a pilot program in August of 2024 and just recently began implementing use of the new testing method. Ohio laws have been revised to permit oral fluid tests, but the testing method has problems.
Revised Laws Authorize Use of Oral Fluid Testing
The testing of alcohol and drugs for DUI cases (called ‘OVI’ in Ohio) is regulated by the Ohio Department of Health. In January of 2023, the Ohio Department of Health regulations in Chapter 3701-53 of the Ohio Administrative Code were revised to authorize testing of oral fluid for alcohol and drugs of abuse.
The admissibility of alcohol and drug tests in court is governed by Ohio Revised Code (ORC) section 4511.19(D). The Ohio legislature recently revised that section. Effective April 9, 2025, ORC section 4511.19(D) authorizes courts to admit evidence of the presence and concentration of alcohol and drugs of abuse in a defendant’s oral fluid. As oral fluid evidence will not be admissible in court until April 9, 2025, it makes sense that OSHP just began implementing the use of oral fluid testing.
How Oral Fluid Testing Works
When a trooper arrests a motorist for OVI, the trooper will ask the motorist to provide a sample of oral fluid. If the motorist consents, the trooper will swab the motorist’s mouth with a swab to collect the oral fluid. The oral fluid sample will be sent to a crime laboratory.
A laboratory technician will then run tests on the oral fluid sample to determine the presence and concentration of alcohol and drugs of abuse in the sample. The results will be given to the trooper and forwarded to the prosecutor for use in the prosecution of the motorist for OVI.
Problems with Oral Fluid Testing
One potential problem with oral fluid testing is related to the type of testing method. If the crime laboratory uses immunoassay testing, that testing method is prone to producing false positive results. However, if the crime laboratory also uses a chromatography testing method, false positives are much less common.
Another problem with oral fluid testing is the drug being targeted. According to the report by NBC4i, the OSHP pilot program is using oral fluid testing to determine if motorists are driving under the influence of marijuana. That seems to make sense, as the drug most commonly involved in Ohio OVI cases is THC (the psychoactive compound in marijuana).
Measuring the concentration of THC in oral fluid is problematic for at least three reasons. First, the level of THC in a person’s oral fluid has no correlation with the level of THC in a person’s blood, and it is THC in a person’s blood which may impair driving. Second, even the level of THC in a person’s blood is not correlated with impairment, according to studies commissioned by the United States government. Third, a person may have THC in their oral fluid from second-hand smoke.
Evaluating the Pilot Program
The NBC4i report states the OSHP pilot program, “is expected to last for about a year and will give the OSHP ample time to reevaluate the tests so they can be implemented correctly.” The OSHP re-evaluation may be affected by legal challenges mounted by Ohio OVI defense lawyers.
About the Author: Shawn Dominy is a leading OVI lawyer in Ohio and the founder of the Dominy Law Firm in Columbus, Ohio. He can be reached through his law firm’s website: Dominy Law Firm.
