Thirteen people have pleaded guilty to helping briefly disable online payment service provider Paypal as part of a protest that authorities say was organized by the hacking group Anonymous.
Ten of the defendants pleaded guilty Thursday to felony and misdemeanor charges of intentionally damaging a protected computer.
If they stay out of legal trouble, the U.S. Department of Justice plans to drop the felony charges, and the defendants will be sentenced to probation a year from now.
Three other defendants pleaded guilty to misdemeanor charges in San Jose federal court and face similar sentences.
Authorities say the 13 defendants acknowledged taking part in a protest organized by Anonymous in December 2010 after the eBay-owned Paypal cut ties to the anti-secrecy website WikiLeaks when it released more than 700,000 leaked government documents.
Stanley Cohen, an attorney for one of the defendants, said the 13 were engaged in an act of civil disobedience that he believes is protected by First Amendment free speech guarantees. They pleaded guilty to misdemeanors and probation rather than risk a felony conviction and possible prison time, Cohen said.
"You got people here who engage in activity they believed was appropriate, responsible and necessary," said Cohen, who is based in New York. "This is another example of political dissent."
Earlier this month, eBay chairman Pierre Omiydar urged prosecutors to show leniency because Paypal recorded thousands of computers attacking its servers.
Denial of service attacks are launched from remote computers commandeered by rogue programs downloaded online for free that bombard a website so that it becomes overwhelmed and unavailable to visitors. Pinpointing the culprits is difficult. The attacks are relatively easy to mount and can be performed by amateurs.
Anonymous also targeted other websites that were either critical of WikiLeaks or had refused to process payments for WikiLeaks, among them MasterCard and Visa. The targets in what it called Operation Payback even included the Swedish prosecutor's office, after warrants for sexual crimes were issued for Julian Assange, the creator of WikiLeaks.
Four men were convicted last year in the United Kingdom for participating denial of service attacks in Operation Payback.
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