When examining motor vehicle collisions and impairment, marijuana is the most common illicit drug identified in drivers and often found in combination with alcohol. (J. Ramaekers, JAMA, V.319, #14,April 10, 2018). Many states are moving toward the legalization of marijuana at an accelerated rate. Given the abundancy of high potency marijuana-based products in the marketplace, the association between marijuana and impaired driving is not likely to subside in the future. The dialog concerning drinking and driving is years ahead of drug-impaired driving. At the heart of this issue is that in America, there needs to be a focus on driving while impaired, regardless of the specific substance involved.
Unlike alcohol, statutes concerning drug-impaired driving vary from state to state. For alcohol, we have an accepted biomarker standard of impairment of .08 which is based in years of science and research. Currently, the United States does not have a biomarker level of impairment for marijuana. This is due to the lack of definitive clinical research into this area. Below is a map of the states that have legalized marijuana for medical and / or commercial adult use and the highlights of all states laws for driving while impaired by drugs. This map was updated as of June 2020.
*State Drugged Driving Law Statutes as of May 2020