PHILADELPHIA Twenty-six Occupy Philadelphia protesters sued the city in federal court Wednesday, contending that their arrests two years ago after police and city workers dismantled their encampment in front of City Hall violated their First Amendment rights of free speech and assembly.

The lawsuit, filed in U.S. District Court, maintains that the arrests of the 26 in the predawn hours of Nov. 30, 2011, were without probable cause. That was proved, the suit contends, by the acquittals of all 26 in April 2012 on charges of failure to disperse, obstructing the highway, and criminal conspiracy.

The suit seeks unspecified compensatory and punitive damages as well as injunctive relief involving the city's handling of the Occupy demonstrators.

Named as defendants in the lawsuit are Police Commissioner Charles H. Ramsey, Deputy Police Commissioner Kevin Bethel, Capt. William V. Fisher, six specific police officers, and up to 25 unidentified officers who were on the scene at the time of the arrests.

City Solicitor Shelley Smith said she had not seen a copy of the lawsuit and could not comment.

The suit was filed by Center City lawyers Paul J. Hetznecker, Lawrence S. Krasner, and Lloyd Long III, who represented the Occupy protesters at trial. All three were among the charter members of what became known as the Occupy Philadelphia Legal Collective, a group of civil rights and criminal defense lawyers who agreed to represent the Occupy members free of charge.

Last night, Krasner called the 26 protesters "American heroes who effectively fought economic inequality for the 99 percent and whose thanks from their government was this bogus arrest."

Hetznecker said the arrests struck at the "very heart of our democracy."

"We live in a dangerous time when the right to gather in protest in a collective voice of dissent is criminalized," he said.

The Occupy movement began in September 2011 - inspired, some said, by the "Arab Spring," in which popular protests challenged or toppled a succession of regimes across the Middle East.

The first Occupy encampment was in a park in the financial district of New York City. The demonstrators targeted the growing power and political influence of international corporations - a trend that protesters maintained had effectively disenfranchised 99 percent of the population.

The idea took off and soon Occupy encampments were springing up in cities across America. The movement arrived in Philadelphia in October 2011 with the establishment of a camp on Dilworth Plaza on the west side of City Hall.

As the tents multiplied and the campsite grew - and Occupy protesters began getting arrested at bank and corporate offices in Center City - city officials began looking for a way to end the encampment.

Early on Nov. 30, 2011, after several days of notices that city workers would clear Dilworth Plaza to make way for a $50 million reconstruction project, the confrontation occurred.

As police began clearing the encampment, Occupy demonstrators began marching north on Broad Street, where more than 50 were arrested at various points from City Hall to Spring Garden Street.

The scenario was similar in many other cities, and so was the outcome: arrests, acquittals, and civil rights suits.

Many of those suits resulted in pricey settlements for the governments or institutions involved.

In September 2012, for example, the University of California agreed to pay $1 million to settle a suit filed by Occupy protesters who were pepper-sprayed at UC Davis. In July, Oakland, Calif., officials agreed to pay more than $1 million to settle excessive-force lawsuits filed by a dozen Occupy demonstrators arrested in 2011.

In the spring, Occupy Wall Street protesters received $350,000 in a settlement with New York City for damaged property and equipment. Other civil rights suits there are pending.

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