Congress
Congress is the legislative branch of the United States government and is responsible for making federal law. It is a bicameral body composed of the House of Representatives and the Senate. This structure reflects the Framers’ decision to balance state equality with population-based representation and to create internal checks on power.
The House of Representatives consists of members elected for two-year terms from congressional districts that are apportioned among the states based on population. The number of House members was capped at 435 by the Reapportionment Act of 1929 (codified at 2 U.S.C. § 2a). At-large elections occur only in states with a single representative. The Senate consists of two senators from each state, serving six-year terms.
The principal function of Congress is to enact laws. A bill must be introduced by a member, referred to committees for review, debated, and approved by majority vote in both chambers. If the House and Senate pass different versions, the bill is reconciled in conference committee. Once both chambers agree, the bill is sent to the President, who may sign or veto it. Congress may override a veto with a two-thirds majority in both chambers. Congress also has the power to propose constitutional amendments, which require approval by two-thirds of both chambers and ratification by three-fourths of the states.
Article I, Section 8 of the U.S. Constitution enumerates congressional powers, including the power to issue currency, regulate commerce, declare war, raise and support armed forces, establish federal courts, and regulate immigration and naturalization. Congress also has authority under the Necessary and Proper Clause to pass laws needed to carry out its enumerated powers.
Each chamber has exclusive powers. The House has the sole power of impeachment, the power to originate revenue bills, and the power to choose the President in the event of an Electoral College tie. The Senate has the power to try impeachments, confirm executive and judicial appointments, and ratify treaties. Both chambers confirm a nominee for Vice President when a vacancy arises.
The Constitution forbids Congress from passing ex post facto laws, bills of attainder, or other measures that deny due process. Taxation is subject to constitutional restrictions, including the requirement that direct taxes be apportioned and that no taxes favor one state over another.
Congress also exercises oversight of the executive and judicial branches. Through hearings, investigations, and committee inquiries, it monitors the effectiveness of laws, evaluates government programs, and checks potential abuses of power.
[Last reviewed in August of 2025 by the Wex Definitions Team]
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