John Henry Browne, an attorney for Staff Sgt. Robert Bales, addresses reporters Wednesday, Aug. 21, 2013, at Joint Base Lewis-McChord, Wash., south of Seattle. Bales faces sentencing for 16 counts of premeditated murder stemming from his March 2012 attack on two villages in Khandahar Province, Afghanistan, with jurors deciding whether he should receive life in prison with the possibility of parole, or without it. AP Photo/Gene Johnson Former pro football player Marc Edwards speaks with reporters Thursday, Aug. 22, 2013, outside the courtroom at Joint Base Lewis McChord, Wash., where Staff Sgt. Robert Bales was being sentenced for the massacre of 16 Afghan civilians last year. Edwards, who played high school football with Bales in Norwood, Ohio, testified Thursday about Bales' "unbelievable leadership." Former pro football player Marc Edwards, left, speaks with reporters Thursday, Aug. 22, 2013, outside the courtroom at Joint Base Lewis McChord, Wash., where Staff Sgt. Robert Bales was being sentenced for the massacre of 16 Afghan civilians last year. (AP) - The U.S. soldier who massacred 16 Afghan civilians during pre-dawn raids last year apologized for the first time for his "act of cowardice," but could not explain the atrocities to a military jury considering whether he should one day have a shot at freedom. Staff Sgt. Robert Bales said he would bring back the victims of his March 11, 2012, attack "in a heartbeat," if possible. "I'm truly, truly sorry to those people whose families got taken away," he said in a mostly steady voice. I can't comprehend their loss. I think about it every time I look at my kids. Bales, 40, did not recount specifics of the horrors, but described the killings as an "act of cowardice, behind a mask of fear, bullshit and bravado," and said he hoped his words would be translated for the villagers, none of whom was in the courtroom. The father of two from Lake Tapps, Wash., was serving his fourth combat deployment when he left his outpost at Camp Belambay, in Kandahar Province, in the middle of the night to attack the villages. He pleaded guilty in June, and the six-member jury is deciding whether his life sentence should include the chance of parole. His attorneys previously made much of Bales' repeated deployments and suggested that post-traumatic stress disorder and traumatic brain injury may have played a role in the killings. But they offered no testimony from medical experts on that point, saying they saw little point in making the case a battle of the experts. Instead, they rested their defense after Bales finished speaking Thursday. Closing arguments were scheduled Friday morning. Saying he was nervous to address the court, Bales sat at the witness stand as his wife cried in the front row of the courtroom. Bales himself briefly became emotional, especially choking up as he apologized to his fellow soldiers. "I love the Army, I've stood next to some really good guys, some real heroes," he said. I can't say I'm sorry to those guys enough. "Nothing makes it right," he added. So many times before I've asked myself. I don't know why. Sorry just isn't good enough. I'm sorry. His statements were not made under oath, which prevented prosecutors from cross-examining him. Bales described in detail the trouble he had readjusting to civilian life after his deployments to Iraq. He became angry all the time, he said, and he was mad at himself for that. "Normal course of life became hard in that, you know, waiting in traffic, terrible," he said. Certain smells would just drive me nuts. Washing the dishes I'd just be mad about, for no reason. He began drinking heavily, hiding bottles and sleeping pills from his wife. He fleetingly began to see a counselor, but quit because he didn't think it was working and he didn't want others to find him weak. His perpetual rage worsened as he deployed to Afghanistan in late 2011, taking steroids while there. He lashed out frequently at junior soldiers, he said, in ways he's now embarrassed about. Bales said he spent almost the entire day before the murders venting his anger by chopping and sawing a large tree that the soldiers had taken down near the base. Bales' lawyers tried to paint a sympathetic picture of the soldier to contrast his own admissions and the testimony of angry Afghan villagers about the horror he wrought. Former pro football player Marc Edwards testified Thursday as a character witness, telling jurors he remembered Bales as a great leader from their high school days in Norwood, Ohio. Wearing the Super Bowl ring he won with the New England Patriots in 2002, Edwards said the slightly older Bales "took me under his wing" and was magnanimous when he took his position at starting linebacker. The jurors on Thursday also heard from two soldiers who served with Bales in Iraq. One described how they sometimes had to collect the bodies of casualties, and how Bales helped carry civilians wounded and killed at the Battle of Zarqa in 2007. Another soldier, Maj. Brent Clemmer, said it was unfathomable to learn that the competent, positive soldier he knew could have committed the killings. "I walked myself into my office, poured myself a glass of scotch, and cried," he said. The defense followed two days of testimony from nine Afghans, who spoke of their lives since the attacks. If Bales is sentenced to life with the possibility of parole, he would be eligible in 20 years, but there's no guarantee he would receive it.