Three years after his arrest in Iraq, the court martial of Army Private First Class Bradley Manning got underway today at Fort Meade, Maryland outside Washington.

While he has already pled guilty to ten of the 22 charges against him in February 2013, Mannings’s trial today addresses the most serious of the charges brought against him, that of aiding the enemy. This charge carries a maximum sentence of life in prison if convicted.

Manning was arrested in May of 2010 in Iraq where he served as an intelligence analyst for the army there. His arrrest came after computer hacker Adrian Lamo told the FBI that Manning admitted in online chats that he had downloaded material from the U.S. database and passed that material on to WikiLeaks.

The material Manning downloaded and gave to WikiLeaks included videos of Iraqi and Afghanistan airstrikes, a quarter million diplomatic cables and a half a million Iraqi and Afghanistan war logs or Army reports. Manning was responsible for the largest set of restricted material ever leaked to the public.

Manning has been in prison since his arrest in 2010. He was first held for almost a year at the Marine Corps brig in Quantico, then moved to Fort Leavenworth in 2011.

Manning chose to have a judge decide in his case rather than have a jury trial. Opening statements are due to be heard as early as this afternoon.

Outside the gates of Fort Meade, a small group of less than two dozen protested for the release of Manning as they stood in the rain carrying signs and placards.