What would you do?
Manning came to the attention of authorities in May 2010 after a confidential informant, later identified as ex-hacker Adrian Lamo of Sacramento, California, came forward with a stunning story.
It began with a message said to be posted by Manning, using the instant message handle "bradass87."
"If you had unprecedented access to classified networks 14 hours a day 7 days a week for 8+ months, what would you do?" it read.
According to testimony, that was purportedly part of a string of instant messages that a person sent to Lamo, who was convicted in 2004 for hacking The New York Times, Microsoft and Lexis-Nexis computer systems.
Over a period of days beginning on May 22, 2010, Lamo testified, he and the man identified as Manning instant-messaged about the release of the documents and videos.
Lamo has said he reported Manning to authorities.
Army Criminal Investigation Command Special Agent David Shaver has testified that the chat logs that Lamo provided to the Army largely matched chat logs found on Manning's computer in Iraq.
Manning was arrested in Iraq on May 27, 2010, and then transferred to Kuwait before being returned to the United States two months later.
He was formally charged on July 6, 2010, with violations of the Uniform Code of Military Justice and the Espionage Act. In March 2011, the military revised the alleged violations and filed 22 charges against Manning.
He was held for months by the military in solitary confinement, a move that drew sharp criticism from Amnesty International and other human rights groups.
It even cost P.J. Crowley his job as State Department spokesman after he said in March 2011 that the conditions of the soldier's detention were "ridiculous and counterproductive and stupid."
Crowley resigned just days later amid reports that the Obama administration was furious over his suggestion that Manning was being treated badly.
President Barack Obama publicly defended the conditions of the soldier's detention, telling reporters that he had been assured by the Pentagon that the conditions were appropriate and met basic standards.
Even so, the outcry grew, with academics, medical professionals and others weighing in as Manning's attorney filed motions to move the soldier from the Marine Corps prison at Quantico.
After 11 months in solitary confinement, Manning was transferred to Fort Leavenworth. He has since been moved to a jail at Fort Meade.
During closing statements last week, attorneys on both sides pointed to a picture of a smiling Manning.
Each had their own take on the man in the cross-dressing image that was taken in 2010 while he was on leave -- just weeks before his arrest.