California’s New Marijuana Laws of 2017 California’s New Marijuana Laws of 2017 If you are a parent, the legalization of marijuana, or cannabis, in California may have raised concerns that your child or teen will now have more exposure and easier access to the drug. You may be on the lookout for symptoms of marijuana use in order to prevent your child from suffering the drug’s negative impacts, which include cognitive deficits that can occur — and may become permanent — if used when the brain is still developing. California voters passed Proposition 64 — also known as the Adult Use of Marijuana Act (AUMA) — into state law in November 2016. This means that California adults aged 21 and older can now legally possess and use — for nonmedical purposes, and with certain restrictions — up to one ounce of marijuana (or eight grams of concentrates). They also can legally cultivate up to six marijuana plants for their personal use within their residence.