WASHINGTON (CNN) -- The attorney for one of two men arrested during last month's G-20 summit for sending Twitter messages to help protesters argues that they were merely passing along public information.
Students run from tear gas fired by police during protests at the G-20 summit in Pittsburgh in September.
The two were relaying to protesters "what routes they might take, where police have said don't go, and things of that nature," said attorney Martin R. Stolar.
Noting that police had made the information available on the Internet, Stolar said, "I don't see any way that you can criminalize passing on information that the police have put out publicly."
Police arrested Elliot Madison and Michael Wallschlaeger in a hotel room about 10 miles from the site of the global summit in Pittsburgh, Pennsylvania.
Authorities said the men had scanners to pick up police and emergency services transmissions, headphones, microphones, maps and computers. According to a criminal complaint, the two communicated with the protesters via Twitter to "inform the protesters and groups of the movements and actions of law enforcement ... in order to avoid apprehension."
They were charged with hindering apprehension, criminal use of a communication facility and possessing criminal instruments. Both have been released on bail.
Stolar said his client was not using a police scanner at the time of the arrest because the information had been posted on the Internet.
The New York home of one of the two self-described anarchists was raided by the FBI on Thursday. After a 16-hour search, agents reported taking computers and hard drives, cameras, gas masks, a slingshot and various beakers and test tubes.
Stolar filed a motion Friday demanding the return of items he said are unconnected to any investigation, including MP3 players and posters of Marx and Lenin, as well as "identifying information of political associates," which he says "are protected by the First Amendment."
On the day the G-20 summit began, hundreds of protesters -- acting without a permit -- attempted a march but ended up skirmishing with police in the streets of Lawrenceville, two miles from downtown Pittsburgh. Police in riot gear used ear-splitting sound trucks and, occasionally, pepper spray to disperse the activists, and made dozens of arrests by the end of the day.
Most of the protests were peaceful, said police, who announced that only 83 people were arrested over the three days of the summit, September 23-25.
Twitter is an online social networking tool that disseminates brief messages to people who sign up for them.
If the case against the two men goes to trial, said CNN senior legal analyst Jeffrey Toobin, "it could form a test of whether new communications technologies are instruments of free speech -- or of illegality."
CNN's Brian Todd contributed to this report.