Arguably the most peaceful and orderly large Occupy Wall Street encampment – a nearly 500-tent occupation on two flanks of Los Angeles City Hall – is scheduled to be evicted at 12:01 a.m. Monday.

While police in cities from Oakland to New York City have clashed, sometimes violently, with the grassroots economic justice movement that sprang up near-spontaneously in October, Los Angeles has until now extended an olive branch. Mayor Antonio Villaraigosa, a former community organizer, has proclaimed that the movement has "awakened the country's conscience."

But even after City Council president Eric Garcetti originally told protesters to "stay as long as you need to," the city has now withdrawn that invitation, citing destruction to the City Hall lawn as one reason to evict protesters.

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"The movement is at a crossroads," Mr. Villaraigosa said on Friday. "It is time for Occupy LA to move from holding a particular patch of park land to spreading the message of economic justice and signing more people up for the push to restore the balance to American society."

Compared to images of a campus cop at the University of California-Davis pepper-spraying a subdued row of protesters, the injuring of an Iraq War vet in Oakland, and other ugly clashes, Los Angeles has taken a "let's be cool" approach where police have largely ignored an encampment which has seen some internal divides, including heated debate over whether pot smoking should be tolerated.

One reason for the hands-off approach is that the stakes are particularly high for the City of Angels. Los Angeles has a long and complicated history of tension between police and citizens, symbolized by the Rodney King beating in 1991, which led to massive riots.

But in more recent years, reforms and improvements have turned the Los Angeles Police Department into a more professional outfit, albeit with occasional missteps. Four years ago, Villaraigosa had to cut short a trade trip to El Salvador to deal with the aftermath of a May Day immigration rally where police beat demonstrators.

Meanwhile, even the de facto founder of the Occupy movement, Canadian magazine editor Kalle Lasn, has called for the protests to disperse next month and come back together when the weather improves in the spring.

But given the congenial southern California climate and largely sympathetic politicians, Los Angeles' protesters have had few incentives to leave, and have given officials few official reasons – like crime or sanitation problems – to act. Indeed, the camp itself has largely steered clear of the kinds of small-time crimes, drug overdoses, and even shootings that have tainted other camps, and which have given other mayors public backing to close down the camps and tear down tents.

It wasn't clear why Villaraigosa chose this moment to act. At the Friday press conference, the mayor and Police Chief Charlie Beck wouldn't say how far police would go to clear protesters – or whether tear gas and rubber bullets would be used.

"The goal is to do this as peacefully as possible," Chief Beck said.

But some Occupy protesters have already indicated that they will resist eviction from the City Hall park.

"Elected leaders should be more concerned about enforcing regulations on banks than enforcing park rules," spokesman Jacob Hay tells the Los Angeles Times. "They should be busy creating jobs, not creating conflict with peaceful protesters."

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