The intelligence oversight committees have subpoena powers. They can get at anyone in any of the executive agencies who might be willing to testify and contradi

The intelligence oversight committees have subpoena powers. They can get at anyone in any of the executive agencies who might be willing to testify and contradict their leadership. The committees also have the power to extract documents from the executive branch. The CIA torture investigation, as fraught as that was, was done by an intelligence oversight committee. CIA even created an airgapped network just for the oversight committee staffers to read CIA documents.