Congress has the authority to independently investigate violations of the law, ethical transgressions, corrupt practices, neglected agency missions, policy failures, and other problems that occur within the government. An independent power to investigate is essential to Congress’s role as a co-equal branch of government under the Constitution. Investigations of agencies and members of the administration also are critical to Congress’ legislative function, as Congress seeks the most accurate information to inform its deliberations. In our study, Agency Conduct hearings are distinguished from Private Sector Oversight hearings by the target of the investigation. We consider both categories to be “investigative oversight.” Agency Conduct hearings are distinguished from Policy hearings largely by whether an assumption of ethical wrongdoing or agency failure exists. Hearings are not classified as Agency Conduct hearings merely because they are contentious. If a committee holds a hearing with the purpose of challenging the content or direction of policy, it is likely to be categorized as a Policy hearing, rather than as an Agency Conduct hearing.