What does Congress do? The House and Senate explained

Congress is the branch of the US government that makes federal law. What it does falls into four jobs: it writes and passes laws, decides how the government raises and spends money, investigates and oversees the executive branch, and holds the power to declare war. It has two chambers, the House of Representatives, with 435 voting members seated by population, and the Senate, with two members from every state. A bill becomes law only if both pass it in the same words.

In short

• Congress has the powers listed in Article I of the Constitution, above all to make laws, tax and spend, and nothing the president or courts do can fund the government without it.
• The House is large, elected every two years and seated by population; the Senate is smaller, elected for six-year terms, and gives each state two seats.
• Each chamber has jobs of its own: the House starts tax bills and impeaches, the Senate confirms appointments, ratifies treaties and holds impeachment trials.

What are Congress's main jobs?

Making laws

Article I opens by putting "all legislative powers" in Congress. A member introduces a bill, a committee studies and amends it, and if both chambers pass the same text it goes to the president to sign or veto. Congress can override a veto with two-thirds of each chamber. Most bills never get a vote; the note on how a bill becomes a law follows one through each step.

The power of the purse

No money can be spent from the Treasury unless Congress passes a law for it. That rule, in Article I, Section 9, makes Congress the government's paymaster. It sets taxes, approves borrowing, and every year passes spending bills, called appropriations, for the agencies. When those bills don't pass in time and no stopgap is agreed, agencies without funding must stop much of their work, which is a government shutdown.

Oversight

Congress also watches how the executive branch uses the laws and money it gives it. Its committees hold hearings, call officials to testify, demand documents, issue subpoenas, and publish reports. Oversight isn't spelled out in the Constitution; it grew out of the power to legislate, since Congress has to know how laws are working to change them.

War and foreign affairs

The Constitution gives Congress the power to declare war, raise and fund the armed forces, and regulate foreign trade. It has formally declared war 11 times, for five wars, the last in 1942. Since then, presidents have sent forces into conflicts under congressional authorizations or on their own authority as commander in chief, and the War Powers Resolution of 1973 is Congress's attempt to keep a say. Where that line falls is one of the long tugs of war covered in the note on the president's powers.

How are the House and Senate different?

The framers built two chambers on purpose. The House was meant to be close to the people, changing quickly with public mood. The Senate was meant to be slower and steadier, a check on the House. Until the 17th Amendment in 1913, state legislatures chose senators; voters have elected them directly since.

	House of Representatives	Senate
Voting members	435, plus 6 nonvoting delegates	100
Seats per state	By population, at least 1	2 for every state
Term	2 years, all seats every election	6 years, a third of seats every 2 years
Minimum age	25	30
Citizenship	7 years	9 years
Led by	The Speaker, elected by the House	The vice president presides and breaks ties; the majority leader runs the floor
Its own powers	Starts all tax bills; impeaches officials; picks the president if no one wins the Electoral College	Confirms judges and senior officials; ratifies treaties by two-thirds; tries impeachments; picks the vice president if no one wins
How it debates	Tight rules set by its Rules Committee	Open debate; most bills need 60 votes to end a [[what-is-the-filibuster

The six nonvoting House members represent Washington, D.C., Puerto Rico, Guam, the US Virgin Islands, American Samoa and the Northern Mariana Islands. They serve on committees but can't vote on final passage.

Every House seat and a third of Senate seats are filled every even year. The elections halfway through a president's term are the midterm elections, which often change which party controls one or both chambers. Which party holds a majority changes with elections, so any statement of control needs its date.

How does representation work in practice?

The two chambers count people in opposite ways, and the gap is large. After the 2020 census, the average House district held 761,169 people. Seats are shared out among the states by population every ten years, and the House has had 435 voting members since the Apportionment Act of 1911 took effect, apart from a brief rise to 437 after Alaska and Hawaii became states in 1959. In the Senate, every state counts the same.

Here is what that means for the largest and smallest states, using the Census Bureau's 2020 apportionment counts:

	California	Wyoming
Apportionment population, 2020	39,576,757	577,719
House seats	52	1
People per House member	about 761,000	about 578,000
People per senator	about 19.8 million	about 289,000

In the House, a Californian and a Wyomingite are represented in rough proportion: one member for about every 761,000 people against one for 578,000. In the Senate, a Wyoming resident has about 68 times the weight of a Californian, because 577,719 people share two senators while nearly 40 million share two. The Senate's equal seats were the price of the small states' agreement in 1787, and Article V protects them: no state can lose its equal vote in the Senate without its own consent.

Because the number of seats per state is fixed for ten years at a time, the lines inside each state matter too. Drawing them is called redistricting, and drawing them for advantage is gerrymandering.

Why does Congress often seem stuck?

Congress was built to make passing laws hard. A bill has to clear two chambers elected on different schedules from different maps, then the president, and in the Senate usually 60 of 100 votes to end debate. When the House, Senate and presidency are held by different parties, little passes without a deal.

Still argued

Whether that difficulty is a feature or a flaw is argued. Defenders say slowness protects minorities and forces broad agreement, so laws that pass tend to last, which is what the framers intended. Critics say the Senate's equal seats and the filibuster let senators representing a minority of the country block what most people want, and that gridlock pushes power toward presidents acting by executive order and courts deciding questions Congress leaves open. Both describe the same design and weigh its costs differently.

Congress is also the branch a democracy leans on most directly: its members face voters more often than anyone else in the federal government, House members every two years.

Check yourself

• Without looking back: name Congress's four main jobs and give one example of each.
• What can the House do that the Senate can't, and what can the Senate do that the House can't?
• Why does a Wyoming voter have so much more weight in the Senate than in the House?

Sources

• The Constitution of the United States: A Transcription — National Archives
• The House Explained — U.S. House of Representatives
• 2020 Census Apportionment Results — U.S. Census Bureau, 2021
• U.S. Census Bureau Today Delivers State Population Totals for Congressional Apportionment — U.S. Census Bureau, 2021
• Proportional Representation — History, Art & Archives, U.S. House of Representatives