Driving and Drugs: Ohio’s Per Se Marijuana Law

Bottle for alcohol extract of cannabis. Label ...

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 DUI 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 Substance Urine Blood
Marijuana 10 ng/ml 2 ng/ml
Marijuana metabolite 35 ng/ml 50 ng/ml
Marijuana metabolite in combination with alcohol or other drugs 15 ng/ml 5 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.

DUI attorney Charles M. Rowland II dedicates his practice to defending the accused drunk driver in Fairborn, Dayton, Springfield, Kettering, Vandalia, Xenia, Miamisburg, Springboro, Huber Heights, Oakwood, Beavercreek, Centerville and throughout Ohio.  He has the credentials and the experience to win your case and has made himself the Miami Valley’s choice for DUI defense.  Contact Charles Rowland by phone at 937-318-1DUI (937-318-1384), 937-879-9542, or toll-free at 1-888-ROWLAND (888-769-5263).  For after-hours help contact our 24/7 DUI HOTLINE at 937-776-2671.  For information about Dayton DUI sent directly to your mobile device, text DaytonDUI (one word) to 50500.  Follow DaytonDUI on Twitter @DaytonDUI or Get Twitter updates via SMS by texting DaytonDUI to 40404. DaytonDUI is also available on Facebook and on the DaytonDUI channel on YouTube.  You can also email Charles Rowland at: CharlesRowland@DaytonDUI.com or write to us at 2190 Gateway Dr., Fairborn, Ohio 45324.