On Monday, Governor Jerry Brown signed a bill into law that closes one “loophole” left by the passage of Proposition 64: the question of toking while driving. While Proposition 64 made it illegal to have an open container of pot in a vehicle, it didn’t specifically address the use of marijuana products while behind the wheel. Although it’s also already illegal to drive while high, Senate Bill 65 specifically prohibits the smoking or consumption of marijuana products while driving or riding in a vehicle. The measure was written by Sen. Jerry Hill (D-San Mateo) in anticipation of the state’s Jan. 1 start of marijuana sales for recreational use. The new law makes a violation punishable with a $70 fine.

It is already illegal to drive while intoxicated with marijuana and to have an open bag of cannabis in a motor vehicle. The new law bans actually smoking marijuana or consuming cannabis edibles while driving or riding in a vehicle. It is similar to open container laws that prohibit drinking while driving.
In proposing the law, Hill cited a 2012 study by the California Office of Traffic Safety that found more weekend nighttime drivers in California tested positive for marijuana than alcohIt is important to understand that legally possessing pot while driving is different than smoking pot while driving. No one–including medical marijuana users–is permitted to drive if they are “high” from consuming pot. Doing so subjects you to California “driving under the influence” DUI of marijuana charges.7ol.

Health and Safety Code 11362.3 HS, enacted as part of Prop 64, prohibits possessing an open container or open package of marijuana while driving or riding in a motor vehicle, boat, or aircraft.8
This basically means that there is an “open container” law applicable to marijuana, similar to the open container laws that apply to alcohol in motor vehicles.
Driving or riding in a car with an open container or package of marijuana is an infraction carrying a fine of up to $250. For minors under 18, it is punishable with community service and drug education