The California Senate has unanimously voted to approve a bill that would prohibit marijuana use in motor vehicles. Senate Bill 65, proposed by state Senator Jerry Hill, would “make drinking an alcoholic beverage or smoking or ingesting marijuana or any marijuana product while driving, or while riding as a passenger in, a motor vehicle being driven upon a highway or upon specified lands punishable as an infraction.”

The bill was drafted in response to concerns over a potential increase in marijuana-impaired driving in canna-legal states. In Washington, the AAA Foundation for Traffic Safety reported that the number of fatal accidents in which marijuana use may have been a factor doubled from 2013 to 2014. "Washington serves as an eye-opening case study for what other states may experience with road safety after legalizing the drug,” Hill said.

Research into marijuana-related traffic accidents is a relatively new field of study. Before 2010, few police departments reported whether or not marijuana use was implicated in accidents. Colorado didn't begin tracking marijuana-related traffic fatalities until 2013, but did report an increase from 39 deaths in 2013 to 68 in 2015. Traditional drug tests have been unable to identify whether or not a driver is stoned at the time of the test, which has made it difficult to determine whether or not marijuana has been a factor in accidents.

Now that the state Senate has approved the bill, it will move to the Assembly for consideration.