A California Supreme Court ruling that cities have the authority to ban all medical marijuana dispensaries within their borders raises the stakes for a ballot measure battle over how Los Angeles should regulate the drug, backers of two measures said Monday.

An attorney for one of the measures says if none of the ballot initiatives pass on May 21, the City Council may revive its previous efforts to ban dispensaries.

“The City Council may be emboldened by the Supreme Court ruling and may seek to prohibit medical marijuana dispensaries all together as they did just a few months back," said Bradley Hertz, who represents the backers of Proposition D, which would allow only the 130 or so dispensaries that opened before a failed 2007 city moratorium on new pot shops.

Last year the council voted to ban the city’s estimated 700 medical pot shops. It later repealed the ban after a group of dispensary supporters collected enough signatures to put a measure on the ballot to overturn it.

Proposition D's supporters include a group of older dispensaries, a labor union of employees who work at those dispensaries and several council members.

An attorney for a competing measure called Proposition D “a Trojan horse” that is designed to shut down most of the city’s dispensaries immediately and then squeeze out the remaining dispensaries through council action and federal drug raids.

Attorney David Welch is supporting Measure F, which would allow unlimited dispensaries so long as they meet certain requirements. He cited a council vote last August that instructed police to work with the federal Drug Enforcement Agency "to deal with medical marijuana collectives." The next month, federal agents raided several pot shops in downtown and Eagle Rock, an area represented by Councilman Jose Huizar, a leading dispensary opponent.

Supporters of Proposition D say the prospect of more federal raids is a concern. But they said that by forcing the majority of the city's dispensaries to close, Proposition D would reduce the nuisance that has helped prompt federal action.

Jane Usher, a special assistant to City Attorney Carmen Trutanich, said if Proposition D passes, the city will not seek to shut down dispensaries that are following the law.

Dispensaries that opened before 2007 would be “immunized and could continue to operate,” Usher said.

She said the proposition “has been sanctioned” by Monday’s court ruling. If the state Supreme Court had ruled that municipalities could not legally ban dispensaries, Proposition D could have been challenged because it would outlaw the majority of the city’s pot shops, she said.

Meanwhile, a medical marijuana advocate said he expects little to change as a result of the ruling.

“This is pretty much what we expected,” said Dale Gieringer, director of the California chapter of the National Organization for the Reform of Marijuana Laws. “There is no definite declaration in California law that dispensaries are permitted. It’s all very indirect and insinuating.”

He said that’s because the task force that came up with the Medical Marijuana Program Act, which was meant to clarify the medical marijuana situation, could not get a consensus on how the drug would be distributed. The law that ultimately passed in 2003 did not permit (nor explicitly prohibit) the type of commercial sales regularly conducted at dispensaries.

“We’re hoping that the state will adopt a state regulation system that will calm local concerns about permitting dispensaries and create clear regulations,” he said. “We’d like to see state regulations like they have in Colorado.”

He does not believe Monday’s ruling will change much. He suspects there will be more bans, but probably in places there are no dispensaries already.

“This has been the de-facto situation for a long time.”

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