A new report from a bipartisan commission set up to scrutinize the unprecedented use of contractors in Iraq and Afghanistan concludes that the United States has wasted tens of billions of the nearly $177 billion that has been spent on those contracts and grants since 2002.

The report, titled "At What Risk? Correcting Over-reliance on Contractors in Contingency Operations," said its estimate may even understate the problem because it may not take into full account ill-conceived projects, poor planning and oversight by the U.S. government, as well as criminal behavior and blatant corruption by both government and contractor employees.

"For many years," the report says, "the government has abdicated its contracting responsibilities - too often using contractors as the default mechanism ... without consideration for the resources needed to manage them."

The commission, chaired by Michael Thibault, former deputy director of the Defense Contract Audit Agency, and former Rep. Chris Shays (R-CT) holds a hearing Monday to review the new report's findings.

About 200,000 contractor employees are working in Iraq and Afghanistan -- a number roughly equal to the American military forces deployed there, according to the report.

Their work includes guarding bases, building facilities, providing food and laundry services, escorting supply and personnel movements, and translating local languages.

The current unprecedented reliance on contractors reflects a reduction in support functions the military provides and urgent needs in the two combat zones, but it occurs at a time when federal capabilities for managing and auditing contracts have suffered from years of staffing cuts and weak inter-agency coordination, the report says.

The commission's co-chairs said prompt reforms are critical for both improving the effectiveness of U.S. operations and for easing the strain on the federal budget.

Defense officials and other witnesses will testify Monday on the tools and procedures used to keep track of the 200,000 contractor employees working in Iraq and Afghanistan. They will also face questions on the competition involved in choosing contracting companies and at what level the projects can be sustained after the U.S. withdraws from the region.

The commission's final report to Congress is due July 2011 and will identify lessons from the past two years of hearings and recommend improvements for future dealings with contractors in wartime operations.

This post originally appeared at Talking Points Memo.