After inspecting the records of 663 randomly selected guards, the GAO found that nearly two-thirds "had at least one expired firearm qualification, background investigation, domestic violence declaration, or CPR/First Aid training certification."
The investigation highlights problems with management and training at the agency which have led to gaping holes in security.
FPS, once part of General Services Administration, was rolled into the Department of Homeland Security in 2003. A 2008 GAO report was highly critical of staff reductions at the agency which, "diminished security and increased the risk of crime or terrorist attacks," in government buildings.
From 2004 to 2007, the agency's staffing was cut by 20 percent.
"FPS is essentially an agency in crisis," the Goldstein told lawmakers at today's hearing. "Over the last five years, since its transformation from GSA to homeland security, they have not received the resources and the staffing that would be required."
"There's been inattention at the highest levels of the department of homeland security to requirements to protecting federal facilities," Goldstein added. "Actions by management over the last couple of years to try and change and improve things had some success but in large measure have been difficult to achieve."
Matt Chandler, a spokesman for the Department of Homeland Security, released a statement to ABC News saying the department "is committed to providing government facilities and employees with a first class security force. The Federal Protective Service (FPS) is charged with that critical mission and DHS takes the concerns raised in the forthcoming GAO report very seriously."
The statement added that FPS is "taking steps internally to address those shortcomings," and taking steps to "line up mission focus in a more cohesive way" by proposing that the FPS be transferred out from under U.S. Immigration and Customs Enforcement to the National Protection and Programs Directorate, "the Department's lead for critical infrastructure protection."
"Consolidating department responsibilities for protecting government facilities will result in expeditious implementation of government-wide physical security policy," Chandler's statement concluded.
In his prepared testimony, which he read at the hearing, Schenkel said that prior to the GAO briefing, the agency had already instituted corrective action, and that he asked FPS' regional directors to "immediately increase the number of inspections of protected facilities in their respective regions and to report directly to FPS Headquarters the specific actions they would take to address and correct contract guard performance issues."
Other measures taken, according to Schenkel, include stepping up random inspections, providing more information to security guards and increasing communication with contract guard companies.
Additionally, Schenkel's testimony says the agency has formed response teams to act within the next 60 days "to identify training gaps in the contract guard force and take immediate steps to close them," develop training schedules for the guards and explore new training and technological advancements.
But the GAO's preliminary report expresses concern that adding more guard inspections might prove challenging, due in part to staffing limitations.
Lieberman joined security officials in stressing that the stakes couldn't be higher.