Legislative oversight is most commonly conducted through congressional budget, authorization, appropriations, confirmation, and investigative processes, and, in rare instances, through impeachment. But the adversarial, often confrontational, and sometimes high profile nature of congressional investigations sets it apart from the more routine, accommodative facets of the oversight process experienced in authorization, appropriations, or confirmation exercises. While all aspects of legislative oversight share the common goals of informing Congress so as to best accomplish its tasks of developing legislation, monitoring the implementation of public policy, and disclosing to the public how its government is performing, the inquisitorial process also sustains and vindicates Congress's role in our constitutional scheme of separated powers and checks and balances. The rich history of congressional investigations from the failed St. Clair expedition in 1792 through Teapot Dome, Watergate, Iran-Contra, Whitewater, and the current ongoing inquiries into Operation Fast and Furious, has established, in law and practice, the nature and contours of congressional prerogatives necessary to maintain the integrity of the legislative role in that constitutional scheme. A review of the historical experience pertinent to congressional access to information regarding the law enforcement activities of the Department of Justice indicates that the vast majority of requests for materials are resolved through political negotiation and accommodation, without the need for judicial resolution. Absent an executive privilege claim or a statute barring disclosure there appears to be no court precedent imposing a threshold burden on committees to demonstrate a "substantial reason to believe wrongdoing occurred" in order to obtain information. Instead, an inquiring committee need only show that the information sought is within the broad subject matter of its authorized jurisdiction, is in aid of a legitimate legislative function, and is pertinent to the area of concern. In the last 85 years, Congress has consistently sought and obtained access to information concerning prosecutorial misconduct by Department of Justice officials in closed cases; and access to pre-decisional deliberative prosecutorial memoranda-while often resisted by the Department-is usually released upon committee insistence as well. In contrast, the Department rarely releases-and committees rarely subpoena-material relevant to open criminal investigations. Typically, disputes are resolved without recourse to an executive privilege claim. Instead, negotiations produce various compromises: narrowing informational requests, delaying the release of information that could have prejudicial consequences on prosecutions, or redacting sensitive materials. However, when Presidents do claim executive privilege, courts have been reluctant to resolve the dispute. Indeed, litigation over the scope of executive privilege in direct relation to congressional oversight and investigations has been quite limited. In total, there have been four cases dealing with executive privilege in the context of information access disputes between Congress and the executive, and two of those resulted in decisions on the merits. The Supreme Court has never addressed executive privilege in the face of a congressional demand for information.