California law regarding possession of marijuana changed in important ways at the beginning of this year. In general, possession of up to one ounce of marijuana will now be charged as an infraction rather than a misdemeanor. In regards to possession of pot while driving, however, there are some factors that can result in more serious charges.
SB 1449, which took effect January 1, 2011, reclassifies possession of an ounce or less of marijuana from a misdemeanor to an infraction. This is important because a misdemeanor comes with higher fines and the possibility of jail time and becomes part of a person's criminal record, while an infraction comes with a small fine and no jail time and does not become part of a criminal record. (Other sorts of infractions include traffic tickets and littering citations.)
California Health and Safety Code 11357(b) pertains to possession of marijuana in general.
Vehicle Code 23222(b) pertains specifically to possession of pot while driving, stating that possession of an ounce or less is charged as an infraction and results in a fine of up to $100.
It's important to keep in mind, however, that if you are pulled over and found to be high from marijuana, then you can be charged with driving under the influence according to Vehicle Code 23152(a). This is a misdemeanor charge which can result in thousands of dollars in fines, jail time, and a conviction on your criminal record. Moreover, DUI for marijuana could also result in felony charges if you have multiple previous convictions or there is a traffic incident involving injuries.
