The proposal would regulate marijuana like   alcohol, with people over 21 years old allowed to grow, buy, sell and possess cannabis - all of which is barred by federal law.

Ammiano, a Democrat in his third month as a state lawmaker, said taxes and other fees associated with regulation could put more than a billion dollars a year into state coffers at a time when revenues   continue to decline.

He said he thinks the federal government could soften its stance on marijuana under the Obama administration.

"We could in fact have the political will to do something, and certainly in the meantime this is a public policy call and I think it's worth the discussion," Ammiano said. "I think the outcome would be   very healthy for California and California's economy."

A spokeswoman for the Drug Enforcement Agency in Washington, D.C., declined to comment on the proposal. A White House spokesman referred to a statement on a question-and-answer section of an Obama   transition team blog that says the president "is not in favor of the legalization of marijuana."

While Californians have shown some tolerance for marijuana, such as use for medical conditions with voters' passage of Proposition 215 in 1996, the proposal will face tough opposition in Sacramento.

A lobbyist for key police associations in the state called it "a bad idea whose time has not come."

"The last thing our society needs is yet more legal intoxicants," said John Lovell, who represents the California Peace Officers' Association, California Police Chiefs Association and California Narcotic   Officers' Association. "We've got enough social problems now when people aren't in charge of all five of their senses."

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