This file has been updated:

House Republicans on Thursday criticized the Obama administration’s delay in nominating inspectors general for several key agencies.

There are currently 10 inspector general vacancies, including five at cabinet-level agencies. Some have been vacant for longer than three years.

“This administration’s failure to fill inspector general vacancies has weakened the effectiveness of the inspector general community, thus exposing American taxpayer dollars to waste, fraud and abuse,” said Rep. Darrell Issa, chairman of the House Oversight and Government Affairs Committee.

Acting inspector generals have filled the vacant slots.

“While acting IGs do a very, very good job, these positions should be filled as speedily as possible,”said Phyllis K. Fong, who testified at the hearing. Fong is inspector general of the Department of Agriculture and chairman of the Council of the Inspectors General on Integrity and Efficiency.

Acting inspectors general may not carry out their duties with as much vigor as those with Senate confirmation, some observers have said.

“Permanent IGs are in a better position to be viewed as credible than are Acting IGs for a number of reasons,” said Jake Wiens, an investigor with the Project on Government Oversight. “One is that permanent IGs are selected for the position on the basis of their qualifications to lead an IG office, whereas a temporary IG may be a good auditor or investigator, but may not be as qualified for a leadership role.”

Some lawmakers asked why the president does not nominate some of the acting inspectors general with successful tenures. Members praised Mary L. Kendall, acting inspector general of the Interior Department, for example. Kendall investigated the department’s role in the 2010 Gulf of Mexico oil spill.

The State Department has been without a permanent inspector general for more than four years, though under its acting leader, Harry Geisel, the number of investigations has increased.

“I’ve always been told the proof of the pie is in the eating and if a person is doing a good job there’s nothing to suggest he or she will not continue to do so,” said Rep. Danny Davis (D-Ill.). “And I would certainly hope the Senate would take that into consideration where there’s a need for permanent placement.”

Issa suggested there could be some vehicle for Congress or the Council of the Inspectors General to install permanent candidates if the White House does not make a nomination. But Brian Miller, inspector general of the General Services Administration, whose office uncovered an $800,000 employee conference, cited the appointments clause of the Constitution as a major legal obstacle in implementing such a vehicle.

Four of the positions have been vacant for more than three years, and some, like State have been led by deputy inspectors for years, which raised concerns of constitutional legitimacy.

Issa said: “If you have somebody ... who was not confirmed but was just thrown in there as the acting, you are so far removed from constitutional legitimacy you have to ask if there is some process to see that somebody is selected who is not just a yes person for that entity.”

“The Administration supports the work and commitment of all of the IG Offices, including those currently being led by Acting IGs, as they strive to ensure that taxpayers are getting the good government they deserve,” said a White House spokesman.

In a letter to President Obama sent Wednesday night, Sens. Kelly Ayotte (R-N.H.) and Marco Rubio (R-Fla.) asked for information on the delays and a time frame on when he expects to make nominations.

“As elected officials, we have a responsibility to ensure that all federal agencies have proper oversight through highly qualified, permanent inspectors general,” the senators wrote.