WASHINGTON — The Army has finished its investigation into how and why Army Sgt. Bowe Bergdahl disappeared from his base in Afghanistan and senior Pentagon leaders have been briefed, including Defense Secretary Chuck Hagel, officials said Friday.

Details about the probe's conclusion have been closely held. But they are likely to lay out whether Bergdahl deserted his post or was "absent without leave" or AWOL. And it could include recommendations on whether Bergdahl should be charged with any criminal violations or forced to leave the Army. Any final disposition will eventually also determine whether Bergdahl gets as much as $300,000 in back pay and other benefits, including continued health care.

Officials said Army Secretary John McHugh could send the case to a military commander who would decide whether it should go before a court martial and what, if any, charges would be filed against Bergdahl.

Bergdahl disappeared on June 30, 2009, reportedly walking away from his unit after expressing misgivings about the U.S. military's role — as well as his own — in Afghanistan. He was captured by the Taliban and held by members of the Haqqani network, an insurgent group tied to the Taliban that operates both in Pakistan and Afghanistan.

On May 31, Bergdahl was handed over to U.S. special forces in Afghanistan as part of an exchange for five top Taliban commanders who were imprisoned at Guantanamo Bay, Cuba. After spending about two weeks recuperating at a U.S. military hospital in Germany, Bergdahl was sent to Brooke Army Medical Center at Fort Sam Houston on June 13. He is now doing administrative duties at the base, awaiting the conclusion of the case.

Officials suggested that the report's findings may not be made public any time soon.

"Sometimes investigations are used in follow-on judicial processes, and therefore are not released until those judicial processes are complete," said Navy Rear Adm. John Kirby, Pentagon press secretary. He added that Hagel's briefing is "informational" and the Pentagon chief is not expected to have input into the investigation or make any decisions on the case.

"The secretary is not going to do arm twisting" in the case, said Kirby of Hagel. "There's no role for him in the process to modify the investigation."

An initial U.S. military investigation in 2009 concluded that Bergdahl deliberately walked away, based on evidence available at the time. Since his release, some former soldiers who served with him have labeled him a deserter and said he should be held accountable for leaving his post. Others have suggested that troops were put in danger, and even killed, as they tried to find Bergdahl.

But there are also those who contend that even if Bergdahl deliberately walked away, his five years in captivity were more than enough punishment for the soldier.

Shortly after Bergdahl was released, Army Gen. Martin Dempsey, chairman of the Joint Chiefs of Staff, left open the possibility that an Army investigation could result in desertion or other charges. Dempsey was briefed on the results of Dahl's investigation earlier this week and Hagel got a similar briefing on Friday afternoon.

Maj. Gen. Kenneth R. Dahl was tasked to conduct an exhaustive investigation into the matter, and spent months interviewing unit members and commanders, and meeting with Bergdahl and his attorney, Eugene Fidell, a military justice expert who is also a visiting lecturer at Yale Law School. He submitted his report in mid-October, setting off a lengthy legal review on his report and how the Army can legally proceed in the case.

The deal to swap prisoners with the Taliban, meanwhile, enraged members of Congress who complained the administration violated requirements to inform lawmakers of any such transfer 30 days in advance.

A report by the nonpartisan Government Accountability Office said the Pentagon broke the law by not telling Congress and using nearly $1 million of a wartime account to make the transfer.

Hagel told Congress that the Defense Department "acted lawfully in the operation to recover Sgt. Bergdahl, a judgment that was supported by the Justice Department."

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