A: IGs differ from other Executive Branch officials in that they are independent and report to both the agency head and the Congress. While IGs are, according to statute, under the general supervision of the agency head or deputy, neither the agency head nor the deputy can prevent or prohibit an IG from conducting an audit or investigation. IGs are authorized to:
Have direct access to all records and information of the agency,
Have ready access to the agency head,
Conduct such investigations and issue such reports as the IG thinks appropriate (with limited national security and law enforcement exceptions),
Issue subpoenas for information and documents outside the agency (with some limited exceptions),
Administer oaths for taking testimony, and
Hire and control their own staff and contract resources within appropriation limits.
Information from the President's Council on Integrity and Efficiency