Last week, 30-year-old Phoenix native Eric Harroun faced a possible sentence of life in prison after the Justice Department accused him of fighting in Syria on behalf of Al-Qaeda.

Amid doubt about those allegations, Harroun suddenly agreed to a plea deal yesterday, and his sentence is quite a bit shorter than life in prison -- he'll be released from jail, be placed on probation for three years, and has to pay a $100 fine.

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-Eric Harroun Remains Jailed

Nearly all of the relevant documents in the case surrounding the new plea agreement are sealed. The original charges Harroun was arrested on, supporting a terrorist organization and conspiring to use a weapon of mass destruction, have been dropped. Harroun pleaded guilty to "conspiracy to violate the laws of the United States related to transfer and control of defense articles and services."

See, months before politicians like President Obama and Senator John McCain started calling for military action against the regime of Syrian President Bashar al-Assad, Harroun, an Army veteran, was arrested for fighting that same regime.

In 2003, Harroun had been honorably discharged from the Army after sustaining some sort of brain injury in a car accident. It's unclear the extent of his injury, although his attorney has said he suffers from headaches and memory loss.

At some point after that, Harroun developed an interest in the Middle East, and the FBI was aware that Harroun started traveling around the region. Court filings from federal prosecutors suggest Harroun may have participated in the Egyptian Revolution of 2011, a citizen uprising involving many types of people, representing many causes.

The FBI apparently watched Harroun a lot more closely when he went to Syria in January of this year and started fighting against the Assad regime, alongside the Free Syrian Army.

Harroun didn't really make a secret of this, as he posted videos and updates on social-media websites. In one, Harroun says, "Bashar Al-Assad, your days are numbered . . . Where[ver] you go, we will find you and kill you." He did media interviews, too.

Amid all this, Harroun voluntarily submitted to interviews with the FBI four times.

According to an affidavit from FBI Special Agent Paul Higginbotham, Harroun said in one of these interviews that "he hated al-Qaeda, that he did not know any al-Qaeda members, and that he would fight against any regime if it imposed Sharia law in Syria because he was opposed to all forms of oppression."

However, it wouldn't be long before the Justice Department announced allegations that Harroun had been fighting on behalf of al-Qaeda.

According to federal prosecutors, media outlets started talking about Harroun, and in one interview, Harroun described a battle in which he had been separated from his rebel group -- many of whom were killed in action -- and was picked up by another group, which he believed was Jabhat al-Nusra.

Although Jabhat al-Nusra also is fighting the Syrian regime, the U.S. government considers it a terrorist organization, due to its ties to al-Qaeda.

Harroun admitted this to the FBI and described how the people from Jabhat al-Nusra "treated him like a prisoner," according to federal prosecutors. Jabhat al-Nusra disarmed Harroun and kept him guarded, he explained. Harroun claimed he spent maybe 25 to 30 days with this group, which eventually accepted him and let him fight alongside them. Harroun explained that he manned a rocket-propelled grenade launcher.

Harroun voluntarily went back to the United States, under the FBI's suggestion, and was arrested. A grand jury ended up indicting him on charges of providing material support to a terrorist organization and conspiring to possess a weapon of mass destruction, that weapon being the RPG.

But not so fast -- a pair of experts on the Syrian conflict said it was highly unlikely Harroun was fighting for Jabhat al-Nusra, despite what he told the FBI and media outlets.

Federal prosecutors provided two experts who did find it plausible that Harroun was fighting for the group, but outside of the admission, Agent Higginbotham conceded in a hearing, per court transcripts, that the charges are "based primarily off of his statements" and that there's no independent evidence to corroborate all of this.

During a bond hearing for Harroun months ago, U.S. District Judge Ivan Davis wasn't convinced that Harroun was fighting "with an organization he believed was al-Qaeda in Syria. Because I think it was clear from the testimony that there is no corroboration for that conclusion."

An assistant U.S. Attorney wouldn't say whether Harroun would have been charged had he only fought for the Free Syrian Army, although Judge Davis pressed him on the question several times.

Harroun's federal public defender, Geremy Kamens explained, "Never, to my knowledge, has the United States ever charged an American citizen for fighting alongside a group that is aligned with the U.S. interest, and that changes the equation with respect to the consideration and evaluation of the danger to this community."

Harroun's sudden plea deal now comes in the wake of the United States' increasing involvement in the situation in Syria. Harroun was sentenced to time served, so he'll be released from custody instead of spending a few years in prison, as the sentencing guidelines suggest.

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