Local governments in California's have legal authority to ban storefront pot shops within their borders, California's highest court ruled on Monday in an opinion likely to further diminish the state's once-robust medical marijuana industry.

Nearly 17 years after voters in the state legalized medical marijuana, the court ruled unanimously in a legal challenge to a ban the city of Riverside enacted in 2010.

The advocacy group Americans for Safe Access estimates that another 200 jurisdictions statewide have similar prohibitions on retail pot sales. Many were enacted after the number of retail medical marijuana outlets boomed in Southern California after a 2009 memo from the U.S. Justice Department said prosecuting pot sales would be a low priority.

However, the rush to outlaw pot shops has slowed in the 21 months since the four federal prosecutors in California launched a coordinated crackdown on dispensaries by threatening to seize the property of landlords who lease space to the shops. Hundreds of dispensary operators have since been evicted or closed voluntarily.

Marijuana advocates have argued that allowing local government to bar dispensaries thwarts the intent of the state's medical marijuana law - the nation's first - to make the drug accessible to residents with doctor's recommendations to use it.