March 15, 2013  -- In the wake of an ABC News report in which victims of the 2009 Fort Hood shooting said that they feel neglected by the military and "betrayed" by President Obama, Republican lawmakers are demanding new information on the administration's handling of the attack's aftermath, including what role the Justice Department may have played in the military deeming the shooting "workplace violence."

"We remain committed to addressing the intelligence and administrative failures leading up to the attack, as well as learning more about the administration's inexplicable decision to charge [suspected shooter] Maj. [Nidal] Hasan's crime 'workplace violence' instead of terrorism," Rep. Michael McCaul (R.-Texas), Chairman of the House Homeland Security Committee, wrote in a letter to Attorney General Eric Holder today. The letter, a copy of which was obtained by ABC News, was co-signed by Rep. Frank Wolf (R-Virg.) and Rep. John Carter (R-Texas).

The letter's authors support awarding Purple Hearts to the military victims of the shooting, something the "workplace violence" designation prevents. The letter was in part prompted by a reference to the Department of Justice made by Army Secretary John McHugh in an ABC News "Nightline" report in February.

"To award a Purple Heart, [the attack] has to be done by a foreign terrorist element," McHugh said then. "So to declare that soldier a foreign terrorist, we are told, I'm not an attorney and I don't run the Justice Department, but we're told would have a profound effect on the ability to conduct the trial."

DOCUMENT: Letter to Attorney General Holder (PDF)

The new letter, which was sent with a copy of the "Nightline" report, poses eight questions to Holder about the decision to classify the shooting as "workplace violence," including, "Did you or any other Justice Department official provide any written or verbal guidance to the Department of Defense recommending charges for Maj. Hasan? If so, what was the nature of that communication and the guidance provided?"

The letter also seeks all documents pertaining to who "was responsible for creating, reviewing or approving any statements, press releases, talking points and/or other communications or policy statements issued by or from any of the following between the afternoon of November 5, 2009 – March 1, 2010 concerning or with respect to the November 5, 2009 Fort Hood attack: The President, White House staff, the Secretary and/or staff of the Department of Homeland Security, Gen. George Casey, the Secretary and/or staff or employees of the Department of Defense (including but not limited to the Army)."

Thirteen people were killed, including a pregnant soldier, and 32 others shot in the Nov. 5, 2009 rampage by the accused gunman, Maj. Nidal Hasan, at the Army base in Killeen, Texas. Hasan, who was in communication with al Qaeda leader Anwar al-Awlaki prior to the attack, now awaits a military trial on charges of premeditated murder and attempted murder. Al-Awlaki has since been killed in a U.S. drone attack in Yemen, in what was termed a major victory in the U.S. efforts against al Qaeda.

READ: Hasan Asked Awlaki If It Was Okay to Kill American Soldiers

Many of the Fort Hood victims have now filed a lawsuit against the military alleging the "workplace violence" designation means that in addition to not receiving Purple Hearts, they are receiving lower priority access to medical care as veterans, and a loss of financial benefits available to those who injuries are classified as "combat related."

Some of the victims "had to find civilian doctors to get proper medical treatment" and the military has not assigned liaison officers to help them coordinate their recovery, the group's lawyer, Reed Rubinstein said in February.

"There's a substantial number of very serious, crippling cases of post-traumatic stress disorder exacerbated, frankly, by what the Army and the Defense Department did in this case," said Rubinstein. "We have a couple of cases in which the soldiers' command accused the soldiers of malingering, and would say things to them that Fort Hood really wasn't so bad, it wasn't combat."

Some of the victims in the lawsuit said they believe the Army Secretary and others are purposely ignoring their cases out of political correctness.

"These guys play stupid every time they're asked a question about it, they pretend like they have no clue," Shawn Manning, who was shot six times that day at Fort Hood, said in ABC News' original report.

"It was no different than an insurgent in Iraq or Afghanistan trying to kill us," said Manning, who was twice deployed to Iraq and had to retire from the military because of his injuries.

An Army review board initially classified Manning's injuries as "combat related," but that finding was later overruled by higher-ups in the Army. Manning says the "workplace violence" designation has cost him almost $70,000 in benefits that would have been available if his injuries were classified as "combat related."

"Basically, they're treating us like I was downtown and I got hit by a car," he told ABC News.

Pentagon Press Secretary George Little has said the Department of Defense is "committed to the highest care of those in our military family."

"Survivors of the incident at Fort Hood are eligible for the same medical benefits as all service members," said Little. "The Department of Defense is also committed to the integrity of the ongoing court martial proceedings of Major Nidal Hasan and for that reason will not at this time further characterize the incident."

A spokesman for new Defense Secretary Chuck Hagel, who was appointed to the position after ABC News' report aired, said the department's position has not changed.