The California Supreme Court today in San Francisco will hear oral arguments over a legal conundrum involving medical marijuana. The city of Riverside wants to ban sale of medicinal marijuana, a decision that may violate state law ensuring legal access to it. At the same time it adheres to federal law banning marijuana’s sale and use.

To Riverside officials opposed to marijuana sales, the answer is pretty simple: “A medical marijuana dispensary constitutes ‘a Prohibited Use’ ” in Riverside’s zoning code, which makes it a public nuisance, the city’s attorneys wrote in a legal brief. “Any use which is prohibited by state and/or federal law is also strictly prohibited,” the attorneys said.

But marijuana advocates, in their own brief, said Riverside officials are prohibiting the distribution of medicine, and that’s against state law.

“Local municipalities are claiming a right to ban acts authorized by the Medical Marijuana Program Act,” the advocates’ brief said. “The MMPA prohibits a municipality from enacting zoning ordinances which totally ban/prohibit conduct expressly authorized and encouraged by the Legislature.”

Attorneys for both sides were unavailable for comment, as the case is pending.

This case has implications beyond this particular legal action, the advocates’ legal brief said. “Suits enforcing or challenging local ordinances banning acts pertaining to the cultivation and distribution of medical marijuana authorized by the MMPA are being litigated within nearly every jurisdiction within the state of California,” attorneys for marijuana advocates said, adding that they’re representing this issue in nine different jurisdictions. Â

Riverside attorneys said the medical marijuana law provides protections for users, but does not expressly require cities to abandon their zoning regulations.

“The Legislature provided that persons who engage in certain medical marijuana activities are not subject to criminal liability” in some cases, the legal brief for Riverside said. State laws, however, “do not … preempt … the authority of local governments under their police power to adopt zoning and land use ordinances defining certain activities as nuisances.”

The Supreme Court hearing today will be broadcast live on the California Channel beginning at 10:15 a.m.