Significantly, while the specific fights this House has had to engage in—such as to get the whistle-blower complaint about the Zelensky call and to see the president’s tax returns—may seem novel, that’s only because of how many novel issues are arising under this president, and how unprecedented this administration’s unwillingness to share information with the Congress has been. But congressional oversight in general is not novel at all. Indeed, the practice of legislative oversight is older than America itself. The British Parliament, in the 17th and 18th centuries, regularly engaged in such investigations, and American colonial legislatures followed suit, assuming “usually without question, the right to investigate the conduct of other departments of the government and also other matters of general concern brought to their attention,” as written by the legal scholar C. S. Potts in the 1926 University of Pennsylvania Law Review. After the adoption of the Constitution, Congress, too, quickly began exercising its oversight authority. As early as 1792, Congress asked the Washington administration for “necessary” “persons, papers and records” to enable it to investigate a military defeat in the Northwest Territory, and James Madison and other Framers voted in favor of the inquiry.

Over the years, the Supreme Court has repeatedly approved of Congress’s exercise of its oversight authority, recognizing that Congress’s power to investigate is “broad,” encompassing “inquiries concerning the administration of existing laws, as well as proposed or possibly needed statutes,” and “surveys of defects in our social, economic or political system for the purpose of enabling the Congress to remedy them.” As the Court explained in 1927, a “legislative body cannot legislate wisely or effectively in the absence of information respecting the conditions which the legislation is intended to affect or change.” Thus, the Court said, “where the legislative body does not itself possess the requisite information—which not infrequently is true—recourse must be had to others who do possess it.”

In 1957 the Court made it clear that just as Congress has the power to investigate in order to determine whether and how to legislate, Congress also has the power to investigate when it is “related to, and in furtherance of” another “legitimate task of the Congress.” Thus, it follows that Congress can investigate when the results of the investigation could lead “to further action on the part of the [Congress] within its constitutional powers,” such as a decision to impeach.

Without this oversight power, Congress’s ability to fulfill its role in our constitutional system would be considerably hampered. For one thing, it would be less effective as a legislative body, deprived of the tools necessary to determine what its legislative priorities should be and how it can legislate most effectively. Indeed, while the oversight efforts that are making the headlines are the ones related to the White House, the House has already this year held nearly 200 hearings and sent more than 430 letters seeking information on a wide range of topics like emergency health care for veterans, abuse at skilled nursing facilities, natural disasters as a result of climate change, the impacts of trade policies on the U.S. economy, and the policies and priorities of the Food and Nutrition Service. In some of these cases, Congress is seeking information that will help it decide whether to pass new legislation; in others, it is trying to ascertain how legislation already passed is being implemented. Both of these are legitimate purposes, and oversight is necessary to both of them.