A former member of a band of hackers faces up to 10 years in prison after pleading guilty Tuesday to a single computer hacking charge.
Jeremy Hammond, 28, of Chicago admitted to participating in more than a half dozen attacks perpetrated in 2010 and 2011 by Anonymous and affiliated groups, according to the U.S. Attorney for the Southern District of New York.
He pleaded guilty to one count of conspiracy to engage in computer hacking and has agreed to pay US$2.5 million in restitution. Hammond, who went by the nickname "Anarchaos," is scheduled for sentencing on Sept. 6.
The plea related to the most prominent of the hacks in which Hammond participated, in which analyst company Stratfor was attacked.
The hackers obtained the information of 860,000 subscribers and later released emails, credit card numbers and the MD5 hashes, or cryptographic representations, of passwords. The credit card data was used to make $700,000 in purchases, according to prosecutors.
Hammond also admitted hacking computer systems belonging to the Federal Bureau of Investigation, the Arizona Department of Public Safety and various other law enforcement agencies and companies.
In an online statement, Hammond wrote that he participated in the hacking campaigns because "I believe people have a right to know what governments and corporations are doing behind closed doors."
"I believe what I did was right," he wrote.
Hammond wrote that the type of plea agreement he signed -- a non-cooperating plea -- "frees me to tell the world what I did and why, without exposing any tactics or information to the government and without jeopardizing the lives and well-being of other activists on and offline."
Anonymous and its offshoot, LulzSec, ran an aggressive hacking campaign in 2011, bragging of their exploits on Twitter and taunting law enforcement agencies trying to track them down. They hit many organizations including the Public Broadcasting System, Sony Pictures Entertainment, Fox Entertainment Group and the U.K.'s Serious Organised Crime Agency.
Law enforcement did catch up with several of the prominent participants. LulzSec leader Hector Xavier Monsegur, also known as "Sabu," was secretly arrested by the U.S. Federal Bureau of Investigation in 2011.
Monsegur pleaded guilty in August 2011 to various hacking charges and agreed to work with investigators, which resulted in several more arrests.
Ryan Ackroyd, Ryan Cleary and Jake Davis, all of whom live in the U.K., were sentenced in London earlier this month for a string of high-profile distributed denial-of-service attacks. They received sentences ranging from 24 to 30 months.
In April, 25-year-old Cody Andrew Kretsinger, of Decatur, Illinois, was sentenced to one year in federal prison for his role in a May 2011 breach of a Sony Pictures website and database by LulzSec.