WASHINGTON (AP) — Army and Pentagon officials said Tuesday there has been no decision on what, if any, criminal charges will be filed against Sgt. Bowe Bergdahl, the soldier who left his post in Afghanistan and was held by the Taliban for five years before being released in a prisoner exchange.

Gen. Mark Milley, head of U.S. Army Forces Command at Fort Bragg, North Carolina, has a broad range of legal options, including various degrees of desertion charges. A major consideration is whether military officials will be able to prove that Bergdahl had no intention of ever returning to his unit — a key element in the more serious desertion charges.

The case is also fraught with politics. Some members of Congress and former members of Bergdahl's unit criticized the Obama administration for trading someone they considered a deserter for five top Taliban commanders held at the U.S. detention facility at Guantanamo Bay, Cuba. If Bergdahl is severely punished, that trade could be called into question again. On the other hand, some believe that five years in Taliban captivity is punishment enough.

Navy Rear Adm. John Kirby said Wednesday that Milley is proceeding "very, very deliberately and in a measured way."

Appearing on MSNBC, Kirby said that Bowe "has not been charged. There is no pressure or rush to judgment here … and we just have to let this decision play out." Kirby said that a decision "is not imminent."

Possible charges and possible punishments:

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ABSENT WITHOUT LEAVE

This would be one of the least serious offenses. Tens of thousands of soldiers have walked away from their posts over the last decade, some for a few hours, others for a weekend or even weeks. Usually if service members are charged with being AWOL, the assumption is that they intended to return to duty. Often they get some type of administrative punishment. In more serious cases they are discharged.

Because Bergdahl was in a warzone, leaving his combat post is a more serious offense than leaving a U.S. military base without authorization for a few days. So officials are likely to go for a more serious charge.

DESERTION WITH INTENT TO AVOID HAZARDOUS DUTY OR TO SHIRK IMPORTANT SERVICE

This is one of the more likely charges. It is more serious than AWOL because it involves deserting a hazardous duty, which includes combat service. Bergdahl left his post during a combat deployment in Paktika province, a far more critical violation because officials could argue that his sudden absence could have endangered other unit members. The charge does not require the military to prove Bergdahl had no intention of returning to his unit.

DESERTION WITH INTENT TO REMAIN AWAY PERMANENTLY

This charge is less likely because the Army would have to be able to prove that Bergdahl left his post and at some point decided he had no intention of returning. Former Army lawyer Greg Rinckey said that would be difficult, particularly since he was taken prisoner by the Taliban and couldn't return to his post even if he wanted to. Rinckey predicted any good lawyer could argue that Bergdahl would have returned but couldn't.

FAILURE TO OBEY A LAWFUL ORDER

This charge and other similar infractions are also likely to be added to bolster the contention that Bergdahl violated regulations and committed a serious breach of military conduct. The military will want to note that deserting a post during wartime, whatever the mitigating circumstances, cannot be condoned.

POSSIBLE PUNISHMENTS

Desertion in a time of war with the intent to stay away is punishable by death. That outcome is almost inconceivable in this case. Only one service member, Pvt. Eddie Slovik, has been executed for desertion since the Civil War. Slovik, 24, was shot by a firing squad in January 1945, but his execution, approved by Gen. Dwight D. Eisenhower, was kept secret for nine years.

Desertion with the intent to avoid a certain duty or shirk a certain service, a more likely charge, carries a maximum penalty of five years in prison, along with a dishonorable discharge and forfeiture of all pay and benefits.

AWOL can carry a broad range of punishments, ranging from a letter in a service member's file, getting extra duties or having pay docked to getting thrown out of the service.

Depending on the charges and court martial proceedings, Bergdahl could receive an honorable, general or other than honorable discharge. That decision can determine whether he loses his rank, or whether he gets as much as $300,000 in back pay and other benefits, including continued health care.

LEGAL PROCESS

Milley is reviewing the results of an investigation by Maj. Gen. Kenneth R. Dahl, and there is no estimated timeline for a decision. Milley can refer charges to a general court martial or decide not to charge Bergdahl at all. If Milley recommends charges and court martial, Bergdahl and his lawyer, military justice expert Eugene Fidell, can also try to plea bargain. Military leaders are likely to take into consideration Bergdahl's five years in enemy hands and could also consider any potential need for continued health or mental health care.

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