In City of Riverside v. Inland Empire Patients Health And Wellness Center, Inc. (May 6, 2013) S198638, the California Supreme Court unanimously ruled the City of Riverside was within its rights to use zoning ordinances to prohibit all marijuana dispensaries from operating within its borders.
The court held that a Riverside City ordinance making all marijuana distribution a prohibited land use and all marijuana dispensaries a public nuisance not to be in violation of Compassionate Use Act of 1996 and the more recent Medical Marijuana Program of 2004.
The court reasoned that local laws banning marijuana distribution were protected by article XI, § 7 of the California Constitution which gives counties and cities the right to make and enforce within its limits all local, police, sanitary, and other ordinances and regulations not in conflict with general laws of California. Because the Compassionate Use Act and the Medical Marijuana Program only shield dispensaries from prosecution under California state laws, local municipalities are free to regulate dispensaries as they see fit, including banning them altogether.