Marijuana
Alcohol has in many years been the drug most often found in the blood of many drivers. However, in recent studies, Marijuana was the most widely used illicit drug by drivers who "drug and drive. Marijuana can have adverse effects on a driver’s brain. It can slow reaction time and impair judgment of distance and time. In the past 5 years since 2017, 11% of drivers killed in accidents had tested positive to THC, an active component in Marijuana.