Marijuana is the most frequently used psychotropic drug in the United States, following alcohol consumption. Its use is becoming socially acceptable as more and more states legalize recreational consumption. Nevertheless, marijuana is still a drug, and individuals must understand that it has adverse health effects and potential therapeutic benefits.

Marijuana can influence a user’s judgment and impair a person’s driving abilities. A significant problem with its consumption and driving is that there is no statistical link to show what level of marijuana in the blood causes impairment. Roadside tests for the appropriate blood alcohol content to show intoxication are well known. No such uniform standard exists for marijuana, however, since the test can show evidence of drug use from days before, even if the individual is not impaired at the time of the incident.

Jurisdictions that permit the use of marijuana have had difficulty creating scientifically logical and criminally relevant laws about drivers who use cannabis lawfully. This dilemma has resulted in three approaches being used to determine drugged driving. They range from the need to show impairment to a per se standard where the person is found guilty of drugged driving if any trace amount of THC is discovered in the blood.

This Article provides a comprehensive guide to marijuana and its consumption. The drug’s components will be explained along with a medical explanation of how marijuana affects the body to produce a “high.” It then focuses on the relationship between marijuana and impaired driving and explain the different approaches used by the states to establish drugged driving.