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Drug Lawyer – Ohio Marijuana Law and OVI [Video]

Dayton DUI Attorney Charles Rowland > DUI Law  > Drugs & Alcohol  > Drug Lawyer – Ohio Marijuana Law and OVI [Video]

Drug Lawyer – Ohio Marijuana Law and OVI [Video]


DRUG LAWYER – Ohio has adopted one of the toughest and least popular marijuana impairment laws in the country. This post will provide an overview of how other states have dealt with the issue.

Zero Tolerance vs. Per Se

Every state has laws dealing with alcohol-impaired driving and drug-impaired driving. But unlike the laws for alcohol-impaired driving, those that address drug-impaired driving are nuanced, difficult to enforce and prosecute and vary substantially by state. In addition to general impairment laws, there are two basic laws that states tend to use when addressing drug-impaired driving:

  • Zero Tolerance laws make it illegal to drive with any measurable amount of specified drugs in the body. These laws are best suited for illegal drugs: if it is illegal to possess or use a drug, then it is reasonable to prohibit driving after the drug has been possessed and used.
    • 16 states have zero tolerance laws in effect for one or more drugs.
  • Per Se laws make it illegal to drive with amounts of specified drugs in the body that exceed set limits.
    • 6 states have per se laws in effect for one or more drugs.

Which States Uses Zero Tolerance?

18 states have zero tolerance or non-zero per se laws for marijuana.

  • 9 states have zero tolerance for THC or a metabolite.
  • 3 states have zero tolerance for THC but no restriction on metabolites.
  • 5 states have specific per se limits for THC
  • 1 state (Colorado) has a reasonable inference law for THC

Ohio’s Approach

Marijuana and OVI in Ohio

Ohio is one of the six states that have a per se law in effect for THC. In addition, Ohio’s per se law allows the government to prove you guilty even if the only thing you have in your system is a non-psychoactive metabolite of marijuana. That’s right, all the government has to prove is that you used marijuana recently enough that the metabolite is in your blood.

If you find yourself accused of a drugged-driving charges, you face the same tough penalties that are in effect for alcohol-impaired driving. And as this site has repeatedly pointed out – Ohio has declared WAR on drunk driving and as the saying goes, “All’s fair in love and war. Call Dayton Drug Lawyer Charles M. Rowland II if you need a warrior on your side.

While it is well established that alcohol consumption increases accident risk, evidence of marijuana’s culpability in on-road driving accidents and injury is far less clear. Although acute cannabis intoxication following inhalation has been shown to mildly impair psychomotor skills, this impairment is seldom severe or long lasting.  According to the US Department of Transportation, National Highway Traffic Safety Administration. State of Knowledge of Drugged Driving: FINAL REPORT. op. cit., “Experimental research on the effects of cannabis … indicat[e] that any effects … dissipate quickly after one hour.”  According to the 2004 National Highway Traffic Safety Administration factsheet, Drugs and Human Performance, peak acute effects are typically reached within 10 to 30 minutes after inhalation.

In Ohio, a person is guilty of OVI if he or she operates any vehicle under the influence of alcohol, a drug of abuse, or a combination of them. Ohio Rev. Code Ann. § 4511.19.  In Ohio the threshold for drugged driving is illustrated in the following table. Ohio’s DUI Per Se Levels Id. § 4511.19(A)(1)(vii); Id. § 4511.19(A)(1)(viii)(I)-(II).

Prohibited SubstanceUrineBlood
Marijuana10 ng/ml2 ng/ml
Marijuana metabolite35 ng/ml50 ng/ml
Marijuana metabolite in combination with alcohol or other drugs15 ng/ml5 ng/ml

The above levels establish a per se level above which a person is considered to be statutorily impaired by marijuana. Ohio’s law represents the imposition of per se laws for drivers who test positive for THC in the blood without additional demonstrable evidence of psychomotor impairment.  Just like with alcohol, the “legal limit” is not linked with any qualities of the individual, including weight, frequency of use, time of last use or the bodies ability to metabolize THC.  The penalties imposed for a violation of the marijuana per se law are equivalent to the penalties for OVI.

Charles Rowland


Charles M. Rowland II has been representing the accused drunk driver for over 20 years. Contact him at (937) 318-1384 if you find yourself facing a DUI (now called OVI) charge.

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