Most substantive criminal law is legislative law. State legislatures and Congress enact laws that take the form of statutes or congressional acts. Statutes are written statements enacted into law by an affirmative vote of both chambers of the legislature and accepted (or not vetoed) by the governor of the state or the president of the United States. State legislatures may also create legislative law by participating in interstate compacts or multi-state legal agreements. An example of this includes the Uniform Extradition Act or the Uniform Fresh Pursuit Act. Congress makes federal law by passing acts and approving treaties between the United States and other nation-states. At the local level, city, town, and county leaders can make laws through the enactment of ordinances.

4.5.1 State’s Authority to Pass Criminal Laws

States are sovereign and autonomous, and unless the Constitution takes away state power, the states have broad authority to regulate activity within the state. Most criminal laws at the state level are derived from the state’s general police powers, or authority, to make and enforce criminal law within their geographic boundaries. Police power is the power to control any harmful act that may affect the general well-being of citizens within the geographical jurisdiction of the state. A state code, or state statutes, may regulate any harmful activity done in the state or whose harm occurs within the state.

4.5.2 Congress’s Authority to Pass Laws

Congress must draw its authority to enact criminal statutes from specific legislative powers and responsibilities assigned to it in the Constitution. The legislative authority may be either enumerated in the Constitution or implied from its provisions. If Congress cannot tie its exercise of authority to one of those powers, the legislation may be declared invalid.

Enumerated powers, for example, the power to regulate interstate commerce, are those that are specifically mentioned in Article I Section 8 of the Constitution. Over the years, however, courts have broadly interpreted the term “interstate commerce” to mean more than just goods and services traveling between and among the states. Instead, interstate commerce includes any activity—including purely local or intrastate activity—that affects interstate commerce. The affectation doctrine maintains that congressional authority includes the right to regulate all matters having a close and substantial relation to interstate commerce. Although the Court has found limits on what affects interstate commerce, Congress has used its broad power to regulate interstate commerce to criminalize a wide range of offenses. They include carjacking, kidnapping, wire fraud, and various environmental crimes.

The implied powers of Congress are those that are deemed to be necessary and proper for carrying out all the enumerated powers. Article I Section 8 of the Constitution states, “Congress shall have Power . . . to make laws which shall be necessary and proper for carrying into Execution the foregoing Powers, and all other Powers vested by this Constitution.” The implied powers doctrine expands the legislative power of Congress, and for that reason, the Necessary and Proper Clause has often been called the “expansion clause.” Due to the implied powers found in the Necessary and Proper Clause, Congress has the authority to pass legislation and regulate a wide variety of activities. Congress must always show that each law furthers one or more enumerated powers. The Court will overturn acts of Congress when it believes Congress has overstepped its constitutional authority. Despite the broad expanse of implied powers, Congress’s authority is limited compared to the state’s police powers.