Research conducted by the National Highway Traffic Safety Administration indicates that drivers under the influence of marijuana are becoming increasingly common on the roads of New York and other U.S. states. The road safety agency’s latest National Roadside Study suggests that the number of motorists under the influence of THC, which is the chemical component of marijuana that gives the drug its intoxicating effects, has risen by 50 percent within the space of just seven years.
NHTSA began producing its National Roadside Survey of Alcohol and Drug Use by Drivers reports in the early 1970s, and they are compiled by collecting breath, blood and oral fluid samples from drivers at 60 locations spread across the United States. These studies have traditionally focused on alcohol impairment, but NHTSA testers began to screen for marijuana and other drugs in 2007.
The NHTSA roadside data reveals that stiffer drunk driving penalties, more diligent law enforcement and powerful public information campaigns have helped to reduce alcohol impairment among drivers by 77 percent since 1973, but the reports also suggest that legislation allowing the medical or recreational use of marijuana has led to a surge in the number of THC-impaired drivers in recent years. During the most recent study, traces of THC were found in the samples collected from about 9 percent of the drivers tested during daylight hours and almost 13 percent of the nighttime drivers.
Criminal charges must be proved beyond reasonable doubt, and prosecutors generally rely on toxicology evidence to meet this burden in drunk driving cases. However, scientists have yet to develop a reliable way of determining whether or not a motorist is impaired by THC, and experienced criminal defense attorneys may seek to have DUI charges reduced or dropped when the scientific evidence supporting them is less than compelling.
