The following is an extract from Lesson 3 of An Introduction to the U.S. Congress. You can get all of the lessons here: https://cffad.org/topic/#congress-part-1
Over the next several weeks, you will learn what Congress must do, can do, and cannot do within the system of checks and balances summarized in Lesson 2. You will also learn two ways that congressional powers have changed over time.
Getting the allocation of powers right can make all the difference between a system of government that prioritizes justice, happiness, and liberty (as in the Preamble to the Constitution) versus an autocracy set up to serve a few powerful families or military leaders.
Last week, we summarize enumerated and denied powers. This week, we list the enumerated powers.
1. Enumerated powers
What Congress can do is set out in Article I, Section 8, and portions of other Articles III, IV, and V.
To provide for the “common defense and general welfare of the United States,” Article I, Section 8 grants Congress the power to:
- Raise funds through taxation (taxes, duties, excise, and imposts) and borrow to pay debts and provide for our defense and general welfare (Spending Clause and Borrowing Clause)
- Regulate commerce with other countries, among the states, and with the indigenous tribes (Commerce Clause)
- Establish rules on naturalization
- Encourage commerce in the following ways
- Establish laws on bankruptcies
- Create and regulate currency (money)
- Maintain standards for weights and measures
- Establish post offices and roads
- Promote science and arts through the protection of intellectual property (copyrights and patents)
- Create the lower courts
- Provide for our defense in the following ways
- Define and punish maritime crimes and war crimes
- Declare war
- Issue letters of marque and reprisal and make rules regarding captures land or waters
- Raise and support an army (limited to no longer than two years)
- Provide and maintain a navy
- Make rules regarding armies and navies
- Organize, arm, train, and call upon the militia to execute laws, suppress insurrections, and repel invasions
- Make all laws that are necessary and proper for carrying out the powers listed above (See Implied Powers in the coming weeks.)
Congress has some power over the organization and staffing of the executive branch.
- This power comes from Article II, Section 2, Clause 2, which says Congress “may by Law vest the Appointment of such inferior Officers, as they think proper, in the President alone, in the Courts of Law, or in the Heads of Departments.” (For more on this subject, see our course on the Presidency, Lesson 3.)
Congress has some control over the judicial branch.
- Article III, Section 1 creates the Supreme Court and gives Congress the power to create or disband courts below the Supreme Court. The first Congress immediately used this power to establish the appellate and district courts through the Judiciary Act of 1789.
- Congress also used the Judiciary Act of 1789 to set the number of Supreme Court justices to a total of six. Congress has changed this number several times, from a low of five to a high of ten. The Judiciary Act of 1869 fixed the number of Justices at nine, with no changes since then.
- Congress has a role in advising and consenting to the appointment of Supreme Court justices (Article II, Section 2, Clause 2).
- It also has the power to impeach those justices (Article II, Section 4).
- Article III, Section 3 gives Congress the power to determine the punishment for treason.
- The framers also set some limits on how Congress may control judicial powers. Some of these are reviewed in the section below.
Congress has the power to admit new states to the union and to make regulations concerning U.S. territories and properties, per Article IV, Section 3.
Congress can propose amendments to the Constitution via Article V.
- The amendment process is difficult. Two-thirds of each chamber must vote for any proposed amendment. After that, three-quarters of the states must ratify the amendment before it is added to the Constitution.
- Alternatively, two-thirds of the state governments could call for a constitutional convention to propose one or more amendments – which would then need to be ratified by three-quarters of the states.
 Naturalization is the legal process of granting citizenship to a non-citizen.
 The language in this part of the Constitution is confusing to modern readers. One interpretation of this clause is that the Letters of Marque and Reprisal Clause gave Congress only the power to license private vessels to make captures while the Captures Clause gave Congress the power to determine what property was subject to capture by both public and private forces. See Wuerth, I. (2009). The Captures Clause.