Since the GAO is accountable only to the legislative branch, it is in a unique position to investigate the military; no other agency can audit Federal departments with the same degree of independence from the President.
[1][2] Two examples of major GAO investigations in the 2000s were the audits of Operation Iraqi Freedom and Defense Department airline reimbursements.
GAO investigations into Operation Iraqi Freedom revealed a number of accounting problems, ranging from the mundane to the severe.
[3] Procurement irregularities included Halliburton charging the government $5 for hot meals they got from a Kuwaiti subcontractor, Timimmi, for $3 each.
Other accounting snafus resulted in the Army losing track of 56 airplanes, 32 tanks, and 36 Javelin missile command launch-units.
Vice President Richard Cheney refused to disclose which individuals and groups met with the Task Force, prompting Walker to sue for the information in Federal court.
But the Center for Effective Government reported that, "Sen. Ted Stevens (R-AK), chairman of the Appropriations Committee, met with GAO Comptroller General David Walker earlier in [2003], and sources have reported that sharp cuts in the GAO $440 million budget were threatened if the lawsuit was pursued further.
[9] The GAO was designed to be independent, and Walker cites several factors insulating his agency from political pressure.
GAO's independence is further safeguarded by the fact that its workforce consists of career civil servants hired on the basis of their knowledge, skill, and ability.
that several lawmakers have threatened in the past year to cut agency funding if it persisted with the controversial lawsuit.
Representative Thomas M. Davis, R-Virginia, asked the Pentagon to present 11 documents relating to contracts in Iraq, among them papers that would prove whether Halliburton benefited from its association with Cheney.
"[12] In contrast, GAO reports show that the Defense Department's 2,200 overlapping financial systems cost $18 billion a year to operate.
[5] In March 2016, the Project on Government Oversight reported that, "The Department of Defense remains the only federal agency that can't get a clean audit".