WASHINGTON (AP) -

The nation's top military officer said Tuesday the Army could still throw the book at Sgt. Bowe Bergdahl, the young soldier who walked away from his unit in the mountains of eastern Afghanistan and into five years of captivity by the Taliban.

Charges are still a possibility, Gen. Martin Dempsey, chairman of the Joint Chiefs of Staff, told The Associated Press as criticism mounted in Congress about releasing five high-level Taliban detainees in exchange for Bergdahl. The Army might still pursue an investigation, Dempsey said, and those results could conceivably lead to desertion or other charges.

Congress began holding hearings and briefings into the deal that swapped Bergdahl for Taliban officials who had been held at Guantanamo Bay, Cuba, and several lawmakers said that President Barack Obama didn't notify them as a law governing the release of Guantanamo detainees requires. White House staff members called key members of Congress to apologize, but that didn't resolve the issue.

Since Dempsey issued a statement Saturday welcoming Bergdahl home, troops who served with the soldier have expressed anger and resentment that his freedom — from a captivity that they say he brought upon himself — may have cost comrades' lives. Troops stood in stony silence at Bagram Air Field when Defense Secretary Chuck Hagel announced Bergdahl's release over the weekend, and many have since insisted that he be punished.

Indiana Senator Dan Coats was with a group of Intelligence Committee members on Tuesday getting a confidential Defense Department briefing about Sgt. Bergdahl and what led up to his capture.

But, the Republican says that's not the bigger question in his mind.  Coats is concerned about the lesson the Taliban is taking away from this.

"We have a policy that not giving the enemy a thought that if they capture one of ours, we will then return many, many of theirs in a multiple, and we returned some pretty bad guys," Coats said.

Coats went on to tell WSBT Radio's morning news the president broke the law by not keeping certain members of Congress in the loop on what was happening with Bergdahl and this prisoner swap.