"We appreciate that the Army and the Justice Department are conducting a criminal investigation of this shooting," said Lieberman. "But that does not mean that the rest of us, including the Senate Committee on Homeland Security, can just sit back and watch."
Without interfering in the existing investigations by the Obama administration, Lieberman cited Congress' duty as a watchdog in launching the probe on whether the shooting could have been prevented.
The probe could put Lieberman, the chairman of the committee, at odds with the administration's wishes. On Saturday, Mr. Obama warned lawmakers not to turn the shooting into a "political theater," prompting the Senate Armed Services Committee to cancel a scheduled closed-door hearing with Secretary of the Army John McHugh and Army Chief of Staff George Casey.
"We are not interested in political theater," said Lieberman. "We are interested in getting the facts and correcting the system."
Specifically, the Senate committee will continue to look into home-grown terrorists, a task which the committee has undertaken since 2006.
"We're very concerned about individuals who are inspired by al Qaeda's ideology and thus seek to carry out terrorist acts even if they are not directed by al Qaeda," Collins said.
Lieberman suspects that the information was not shared by either "restrictive rules about the sharing of information or just, sort of, bureaucratic inertia or stovepiping."
"If it could be seen together in a, kind of, flashing neon light, 'this man is about to do something terrible,'" said Lieberman. "That's the question we have to ask and hopefully answer."
While the post-9/11 procedures have expanded the sharing of information between agencies, the FBI has the last word on whether information is to be shared.
"The members of these task forces are prohibited from sharing information with their home agencies unless they get explicit permission from the FBI," said Collins. "Should it have been shared? Did the FBI allow for it to be shared?"