Charles K. Edwards issued a statement on Tuesday denying the claims and insisted that they are "completely without merit."
"I am very disturbed that false allegations have been made against me, but more importantly, I am very concerned that this matter may negatively impact the important oversight work of the Office of Inspector General," Edwards said in a statement from Chennai, India, where he was vacationing with his family.
In a letter sent last week, Sens. Claire McCaskill, D-Mo., and Ron Johnson, R-Wis., the chairwoman and ranking member of the Senate Homeland Security financial and contracting oversight subcommittee, detailed nine allegations against Edwards and asked him for information so that they can investigate.
Among the allegations, the letter said whistleblowers have told the subcommittee that Edwards employed his wife, Madhuri Edwards, in a top job in his office violating nepotism laws, used government vehicles for personal chores and threatened retaliation when he was confronted by staff.
The letter also says whistleblowers accused Edwards of being "susceptible to political pressure" after he allegedly massaged and withheld potentially damaging information from an investigation into the Secret Service scandal involving prostitutes in Cartagena, Columbia.
Edwards said the allegations against him are "not new."
"Many have been the subject of Freedom of Information Act requests, media reports, and Congressional inquiry," he said. "Similar allegations were reviewed and dismissed by various oversight bodies including the Council on Inspectors General on Integrity and Efficiency."
In their letter, McCaskill and Johnson request that Edwards comply with a series of information requests by July 19.
Copyright 2013 The Associated Press.