The arrest of a New Yorker for using Twitter to alert protesters to police movements at a meeting of world leaders in Pittsburgh last month would be deemed a human rights violation if it happened in Iran or China, rights activists charge.

Pittsburgh police arrested Elliot Madison, 41, on September 24 as hundreds of people -- some throwing rocks and breaking shop windows -- protested on the first day of a summit of the Group of 20 rich and developing nations.

The protesters, with a broadly anti-capitalist agenda, were kept well away from the convention site where the leaders held their two-day meeting. Police sporadically used pepper gas to disperse them.

The criminal complaint against Madison said he broke the law by using Twitter to direct unlawful protesters and other people involved in criminal acts to avoid arrest and to inform them of police movements and actions. Twitter allows subscribers to publish 140-character text messages.

Madison, who was released on bail, is charged with hindering apprehension or prosecution, criminal use of communication facility and, possessing instruments of crime -- defined as telecommunications equipment.

The same conduct (of authorities) in Iran or China during recent demonstrations would be called human right violations whereas here it's called necessary crime control, Vic Walczak, legal director of the American Civil Liberties Union of Pennsylvania, told Reuters. It's a real double standard.

Twitter was used by protesters in Iran amid the protests and government clampdown that followed the country's disputed June elections. At one point, the U.S. State Department even urged Twitter to delay a planned upgrade that would have temporarily cut service to Iran.

China has blocked access to online sites such as Twitter several times, including in May ahead of the 20th anniversary of the Tiananmen Square crackdown and again in July following ethnic unrest in the northwestern region of Xinjiang.

Pittsburgh police, asked about what was illegal about Madison's actions, noted the charge that Madison was hindering apprehension or prosecution by law enforcement.

All law enforcement agencies must keep abreast of constant developments in technology, both for determining how technology can help police better serve the public and for uncovering ways in which technology can be used to commit crime, spokeswoman Myra Taylor said. The criminal complaint alleges that Mr Madison used legal devices to perform illegal acts.

Laura DeNardis, executive director of Yale Law School's Information Society Project, said Madison's arrest could be used by repressive countries who may be looking to crack down on technologies.

They might cite this as a justification for thwarting free speech in even more direct ways and for cracking down in cases like we saw in the Iranian election protests, said DeNardis. To me this seems like a double standard.

Madison was arrested in a Pittsburgh motel, but authorities raided his home in the New York City borough of Queens on Thursday and his lawyer Martin Stolar went to Brooklyn Federal Court on Friday to ask for the return of property taken.

It's an outrageous use of criminal law to punish dissent, to punish speech, which tends to support dissent, and it is the most unique application of the criminal law to the use of Twitter that I have ever seen, said Stolar.

Essentially we have Elliot accused of taking publicly available information and giving it to another person in the public and then being charged with a crime for doing so, he said. I'm missing something here.

The ACLU's Walczak said the case could also have repercussions for the media.

In this age of instant media coverage it has the potential to chill live reporting. This is just the rebroadcasting of information that's otherwise publicly available, not too different from what the media were doing.

(Editing by Mark Egan and Frances Kerry)

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