Anthony Bolante / Reuters

Attorney John Henry Browne, right, discusses the case of Staff Sgt. Robert Bales in Seatttle on Friday. With Browne is associate counsels Emily Gause.

An attorney for Army Staff Sgt. Robert Bales, who has been charged with killing 17 Afghan civilians in two villages, said Friday that the defense team is “facing an almost complete information blackout from the government,” which is having a “devastating effect” on their investigation.

Bales, a 38-year-old father of two, is accused of creeping into the villages at night on March 11 and attacking the villagers. The Army has charged him with 17 counts of murder, six counts of attempted murder and six counts of assault. Nine children, four men and four women, were slain.

“We are facing an almost complete information blackout from the government which is having a devastating effect on our ability to investigate the charges preferred against our client,” his civilian attorney, John Henry Browne, said in a statement. 

Maj. Chris Ophardt, a spokesman for 1st Corps, Joint Base Lewis-McChord in Washington, said the investigation was ongoing.

“The prosecution will provide the defense with evidence in accordance with the Rules for Courts-Martial and the Military Rules of Evidence. Within these guidelines the prosecution is and has been communicating with the defense,” he said in an e-mail. 

Browne, who is in Seattle, was speaking about members of the defense team in Afghanistan. He said they had tried to interview injured civilians being treated at Kandahar Hospital but were denied access and told to coordinate with prosecutors. He said that the following day, the prosecution team interviewed the wounded, with defense counsel only later learning that they had been released from hospital and there was no contact information for them.

“These witnesses are now who knows where … people just disappear into the countryside in Afghanistan,” he said later Friday at a press conference. “They (prosecutors) actually promised us that if we sent people to Afghanistan … that they would cooperate and make witnesses available for us, and they obviously violated that promise.”

Browne also said in the statement that his team was denied access to medical records of the wounded, making it “even more impossible” to locate them, and that the prosecution was “withholding the entire investigative file from the defense team.”

Afghan massacre: Sgt Bales case echoes loudly for ex-soldiers on hotline for vets

 The Army doesn’t have any requirement to provide evidence to the defense at this point, according to military rules governing courts-martial. The next stage of the legal process is the Article 32 hearing, akin to a civilian grand jury, and which is “supposed to be a discovery tool for the defense,” Michael Navarre, an adviser at the National Institute of Military Justice and a former Navy prosecutor and defense counsel, told msnbc.com.

In general, most military prosecutors are cooperating with the defense and will provide some information -- though not everything -- prior to the Article 32 hearing to ensure it goes smoothly, he added, noting that some evidence may even be discovered after that proceeding.

“As a defense counsel, one of your jobs is to … build a public record as to what the government’s doing during the course of their investigation and also to some degree build sympathy for your client,” he said. “Given the seriousness and the gravity of the charges against his client, I would say it’s not uncommon to point out that the government isn’t being cooperative with your client in the investigation given the current public perception of his client.”

Browne said that though the defense team didn’t have the right to certain discovery materials until 30 days before the Article 32 hearing, he’d had better dealings in the past with prosecutors.

“We usually have the cooperation of prosecutors and they will give us information ahead of time just so we can be prepared and that’s just not happening in this case,” he said at the press conference. “My gut, from a defense lawyer’s standpoint, is when the prosecutors are not cooperating there’s a reason, and that reason usually is because they don’t really have much of case.”

“If they want cooperation from us, they better start cooperating more,” he later added.

How Staff Sgt. Bales' lawyers are fighting for his life

Bales, of Bellevue, Wash., is being held at a U.S. military prison in Fort Leavenworth, Kan. He was on his fourth tour in a war zone since signing up for the Army after the 9/11 terrorist attacks in 2001. He had been in Iraq on his previous tours, during which he suffered a foot injury and a traumatic brain injury in a vehicle rollover, media reports say.

Browne said Bales was “holding up,” communicating with his wife, being treated well. He said Bales had seen a chaplain.

Some military law experts interviewed by msnbc.com said they expect the defense to mount a legal pincer attack, in which Bales’ attorneys may try to win acquittal by attacking the evidence but have a fallback position aimed at winning a lesser sentence than the death penalty -- which Defense Secretary Leon Panetta has said could be sought in this case.

That fallback position could be diminished mental capacity, which they may attribute to his reported combat injuries and mental trauma.

For alleged Afghan shooter, death penalty unlikely

U.S. military officials told NBC News on Friday that the Army was preparing to conduct a psychological exam of Bales. The exam, known as the “706 Board,” is considered routine in such cases and will include a team of psychiatrists.

It's likely Bales would remain at Fort Leavenworth and the board doctors would travel to him, though a final decision has not been made.

NBC’s Chief Pentagon Correspondent Jim Miklaszewski and news producers Karen Lucht and Courtney Kube contributed to this report.

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