NEW YORK, Nov 18 (Reuters) - In the wake of the surprise early-morning police sweep of Zuccotti Park on Tuesday, lawyers for the Occupy Wall Street protesters, the city, and the park's owner are all confronting an intriguing question: Is sleeping overnight in public spaces a protected form of free speech? And if it is, can the government still stop people from doing it?

At the Tuesday afternoon hearing following the sweep, the protesters' lawyers argued that the overnight nature of the protests was itself a type of speech, and challenged the city's contention to the contrary.

"They'd like to say it's a camping case," said Alan Levine, a civil-rights lawyer representing the protesters before State Supreme Court Justice Michael Stallman. "It's not a camping case, it's a First Amendment case. They're sleeping there 24 hours a day as a form of expression."

But over the past several decades, a handful of cases -- including one decided by the U.S. Supreme Court -- have grappled with that question, which sits at the intersection of the First Amendment and the government's interest in maintaining law and order on public property.

The issue seems likely to be a central point of contention as the legal battle over Zuccotti Park proceeds. Although Stallman refused to extend the restraining order that had been issued earlier Tuesday morning, the protesters' underlying petition for relief remains pending. Papers in opposition and support from both sides are due Dec. 1.

SUPREME PRECEDENT

In the Supreme Court case, Clark v. Community Creative Non-Violence, decided in 1984, protesters petitioned for the right to sleep overnight on the National Mall in Washington as a way of calling attention to homelessness.

The Court held 7-2 that, even assuming sleeping was a protected form of speech, the Park Service's interest in maintaining the space was substantial and the rules narrow enough to justify preventing the protesters from sleeping there as a reasonable "time, place and manner" restriction. Such restrictions may be permitted if they are content-neutral, serve a state interest, and are narrowly drawn so as to allow other means of expression.

By contrast, in a 2000 case in Manhattan federal court, Metropolitan Council v. Safir, U.S. District Judge Kimba Wood ruled that a tenants' advocacy group had the right to sleep overnight on sidewalks near the mayor's home to protest proposed increases for rent-stabilized apartments.

Finding that a complete ban on sleeping on sidewalks was too broad, Wood held that the city's interest in keeping pedestrian traffic unimpeded would be maintained if the protesters kept their promise of sleeping on only half the sidewalk, allowing people to walk past.

Gideon Oliver, a lawyer for Occupy Wall Street, said Thursday that protesters could use Metropolitan to argue that the Brookfield rules are too expansive.

He also pointed out that in Clark, the Park Service's rule prohibiting camping outside of designated campgrounds predated the protesters. Zuccotti Park's sleeping ban was established only after the protesters had set up camp.

'A REAL STRETCH'

But Floyd Abrams, a prominent First Amendment expert with Cahill Gordon & Reindel, said he is not convinced that sleeping could be considered a form of speech.

"It seemed to me a real stretch to maintain that sleeping in a designated area itself is anything more than what it appears to be," he said.

Even if sleeping is expressive, Abrams said, the city would still have a relatively strong argument that removing the protesters' camp was necessary to keep the park accessible and to protect residents.

"I'm still of the view that they never had a legally enforceable right to establish themselves as semi-permanent residents of the park," Abrams said.

Before protesters make their case that sleeping overnight is speech, however, they will need to establish that free-speech rights are fully protected in Zuccotti Park in the first place.

Under Supreme Court precedent, they have to show that the park is not a "limited" public forum, but a "traditional" one, which would ensure that any challenge to the First Amendment is subject to strict scrutiny. Sidewalks and public parks are classic examples of traditional public forums. The same is not necessarily true of other areas open to the public.

In 2002, the federal appellate court in New York denied permission to a union seeking to stage a rally on the Lincoln Center plaza. The Second Circuit Court of Appeals ruled that the space had historically been used solely for artistic purposes and was therefore a limited, not a traditional, public forum. In such cases, restrictions on speech are only subject to strict scrutiny if the speech falls into the designated category for which the forum exists -- in the case of Lincoln Center's plaza, artistic expression.

PARK'S UNUSUAL STATUS

The question in the current case is complicated by Zuccotti Park's unusual status: under a zoning deal struck with the city, it is a privately owned space that must be open to the public at all times. The company Brookfield Properties owns the plaza but operates it essentially as a public park, although without the curfews that exist in public parks.

At Tuesday's hearing, Oliver argued that the park's four-plus decades as a round-the-clock public space suggested that protesters should be accorded full First Amendment protection. That is, Brookfield and the city would have to demonstrate a genuine state interest to impinge on protected expression -- such as a threat to public safety -- and could only institute rules that restricted such speech in the "least drastic manner possible," Levine argued.

But Brookfield's lawyer, Douglas Flaum, and city attorney Sheryl Neufeld argued that the park has no history of being used for demonstrations and therefore should not be considered a traditional public forum. Nevertheless, Flaum and lawyers for the city said, they had no problem with allowing protests at the park as long as the encampment was removed.

The city also argued that the presence of electrical wires, wooden pallets and cigarettes created a safety hazard that could only be remedied by the removal of the entire camp.

The city took photographs of what officials said were fire hazards around 2 p.m. Monday, less than 12 hours before the raid began, and included them as court exhibits in its filing Tuesday.

"If there were a fire, people could not get out in an orderly fashion," Neufeld said in court.

'LESS RESTRICTIVE ALTERNATIVES'

But Levine said in court that "there are less restrictive alternatives," arguing that the city could take steps to ensure safety and health at the plaza without evicting the entire encampment.

In his ruling Tuesday, Judge Stallman assumed that the protesters had full First Amendment protection at the plaza but found nevertheless that Brookfield's rules against tents and lying down were reasonable restrictions to maintain a clean, safe and accessible park.

The protesters, he wrote, "have not demonstrated that the rules adopted by the owners of the property, concededly after the demonstrations began, are not reasonable time, place, and manner restrictions permitted under the First Amendment."

(Reporting by Joseph Ax)

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