Powers and Duties of the United States Congress

Setting the Rules and Laying Down the Law

Woman walks on fountain near U.S. Capitol
Woman Walks on Fountain Near U.S. Capitol. Mark Wilson / Getty Images

So what are all those senators and representatives doing on Capitol Hill, anyway? The Congress has specific powers spelled out in the Constitution, none more important than its duty to make laws.

Article I of the Constitution sets forth the powers of Congress in specific language. Section 8 states, "Congress shall have Power … To make all Laws which shall be necessary and proper for carrying into Execution the foregoing Powers, and all other Powers vested by this Constitution in the Government of the United States, or in any Department or Officer thereof."

Making Laws

Laws aren't simply conjured out of thin air, of course. In fact, the legislative process is quite involved and designed to ensure that proposed laws are given careful consideration. 

Briefly, any senator or congressman may introduce a bill, after which it is referred to the appropriate legislative committee for hearings. The committee, in turn, debates the measure, possibly offering amendments, then voting on it. If approved, the bill heads back to the chamber from which it came, where the full body will vote on it. Assuming lawmakers approve the measure, it will be sent to the other chamber for a vote.

Once the measure clears Congress, it is ready for the president. If both bodies have approved legislation that differs, it must be resolved in a joint congressional committee before being voted on again by both chambers. The legislation then goes to the White House, where the president may either sign it into law or veto it.

Congress, in turn, has the power to override a presidential veto with a two-thirds majority in both chambers.

Amending the Constitution

In addition, Congress has the power to amend the Constitution, though this is a long and arduous process. Both chambers must approve the proposed constitutional amendment by two-thirds majority, after which the measure is sent to the states.

The amendment must then be approved by three-quarters of state legislatures.

The Power of the Purse

Congress also has extensive powers over financial and budgetary issues. These powers include:

  • levy and collect taxes, duties, and excise fees;
  • allocate money to pay the government’s debts;
  • borrow money on the credit of the United States;
  • regulate commerce between the states and other nations;
  • coin and print money; and
  • allocate money to provide for the common defense and general welfare of the United States

The Sixteenth Amendment, ratified in 1913, extended Congress’ power of taxation to include income taxes.

Its power of the purse is one of Congress' primary checks and balances on the actions of the executive branch

Armed Forces

The power to raise and maintain armed forces is the responsibility of Congress, and it has the power to declare war. The Senate, but not the House of Representatives, has the power to approve treaties with foreign governments, as well.

Other Powers and Duties

Congress keeps the mail moving by establishing post offices and the infrastructure to keep them going. It also appropriates funds for the judicial branch. Congress can establish other agencies to keep the country running smoothly as well.

Bodies such as the Government Accountability Office and the National Mediation Board ensure that the monetary appropriations and the laws that Congress passes are applied properly. Congress can also investigate pressing national issues, famously holding hearings in the 1970s to investigate the Watergate burglary that ultimately ended the presidency of Richard Nixon, and it is charged with supervising and providing a balance for the executive and judicial branches.

Each house has some exclusive duties as well. The House can initiate laws that require people to pay taxes and can decide whether public officials should be tried if accused of a crime. Representatives are elected to two-year terms, and the Speaker of the House is second in line to succeed the president after the vice president.The Senate is responsible for confirming presidential appointments of Cabinet members, federal judges and foreign ambassadors.

The Senate also tries any federal official accused of a crime, once the House determines that a trial is in order. Senators are elected to six-year terms; the vice president presides over the Senate and has the right to cast the deciding vote in the event of a tie.

In addition to the explicit powers enumerated in Section 8 of the Constitution, Congress also has additional implied powers derived from the Necessary and Proper Clause of the Constitution.

Phaedra Trethan is a freelance writer who also works as a copy editor for the Camden Courier-Post. She formerly worked for the Philadelphia Inquirer, where she wrote about books, religion, sports, music, films and restaurants.