#3 Mark Klein

Leak: Location of secret NSA wiretap room at AT&T (2006)

Mark Klein is a former AT&T technician who leaked knowledge of his company's cooperation with the United States National Security Agency in installing network hardware to monitor, capture and process American telecommunications. The subsequent media coverage became a major story in May 2006.

In recognition of his actions, the Electronic Frontier Foundation picked Klein as one of the winners of its 2008 Pioneer Awards.

#2 Bradley Manning

Leak: 250,000 U.S. diplomatic cables, videos of U.S. military airstrikes (2010)

Bradley Edward Manning is a United States Army soldier who was arrested in May 2010 in Iraq on suspicion of having passed classified material to the website WikiLeaks. He was ultimately charged with 22 offenses, including communicating national defense information to an unauthorized source and aiding the enemy.

Assigned to an army unit based near Baghdad, Manning had access to databases used by the United States government to transmit classified information. He was arrested after Adrian Lamo, a computer hacker, told the FBI that Manning had confided during online chats that he had downloaded material from these databases and passed it to WikiLeaks.

Manning was held from July 2010 in the Marine Corps Brig, Quantico, Virginia, under Prevention of Injury status, which entailed de facto solitary confinement and other restrictions that caused international concern. In April 2011 he was transferred to Fort Leavenworth, where he could interact with other detainees. He pleaded guilty in February 2013 to 10 of the 22 charges, which could carry a sentence of up to 20 years. The trial on the remaining charges, including aiding the enemy, began on June 3, 2013.

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