He also noted that other council members had proposed numerous amendments. "This is only the tip of the iceberg," he said.

Councilman Ed Reyes, who is overseeing efforts to craft a law, introduced a motion that would make a series of major changes to the proposal, and asked that the council take more time to review them.

The Los Angeles City Council this afternoon postponed a vote on a medical marijuana ordinance until next week at the earliest.

William Carter, chief deputy city attorney, agreed that it would be helpful for his office to have time to review the proposed changes to the ordinance that two committees sent to the full council on Monday.

Among the amendments is one that would reduce the distance to 500 feet from 1,000 feet that dispensaries must maintain from schools, parks, libraries and other places where children gather.

A city study showed that only a quarter of the 186 marijuana dispensaries legally operating under the moratorium adopted in 2007 would be able to meet the 1,000-foot requirement.

City officials have struggled for more than two years to write a law to regulate the dispensaries, which have proliferated across the city. Advocates say state law allows the collectives to sell marijuana to members who have a doctor's recommendation.

But Los Angeles County Dist. Atty. Steve Cooley says state laws do not allow dispensaries to exchange marijuana for cash, and has vowed to prosecute them even if Los Angeles officials adopt a measure allowing the stores to operate.

Discussion is continuing this afternoon in the council chambers.

-- John Hoeffel at Los Angeles City Hall

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