Seth Wenig, Associated Press
Kevin Alvarez, left, and his lawyer Jethro Eisenstein smile as his case is dismissed in Manhattan Criminal Court in New York, Monday, Jan. 9, 2012. Alvarez was in court for his participation in an Occupy Wall Street protest. New York prosecutors have dropped charges against nearly two dozen people arrested in the first mass arrest of Occupy Wall Street demonstrators.

NEW YORK — Prosecutors dropped charges Monday against nearly two dozen people picked up in the first mass arrest of Occupy Wall Street demonstrators, but about 50 other cases are headed toward trial.

The Manhattan district attorney's office asked a judge Monday to dismiss 21 cases stemming from a Sept. 24 march to Manhattan's Union Square. Prosecutors said they couldn't prove beyond a reasonable doubt that those individuals' conduct was illegal. They faced charges of disorderly conduct, a violation.

The march came a week after the protest began at Manhattan's Zuccotti Park. The about 80 arrests helped draw attention to the movement after activists posted an online video that showed a police official using pepper spray on a small group, mostly women, whom officers had corralled behind orange netting near Union Square.

Authorities said the demonstrators blocked car and foot traffic and rebuffed orders to disperse.

Police "made repeated requests for the protesters to get onto the sidewalks and to keep moving, both of which requests were loudly and entirely refused," Assistant District Attorney Ryan Hayward wrote in court papers filed Monday in one of the cases that wasn't dismissed.

But many protesters say they followed police instructions.

"I was quite shocked" to be arrested, said Robert Hott, 26, whose case was dismissed. He said he hadn't heard any order to leave that day.

Hott said he'd never been arrested before, and he stayed away from later Occupy marches because he didn't want to get arrested again.

"It's definitely a deterrent" to demonstrating, he said.

About a dozen others previously took prosecutors' offers to get the charges dismissed by staying out of trouble for six months.

Many of those whose cases remain open are asking Manhattan Criminal Court Judge Neil Ross to dismiss them, with many arguing that the police orders were ambiguous. Ross set a Feb. 22 date to address those arguments and some other legal issues, said Martin Stolar, a lawyer representing some of the demonstrators.

More than 1,200 people have been arrested in connection with Occupy protests in New York City, including more than 700 people picked up in an Oct. 1 march on the Brooklyn Bridge.

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