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Most of the laws come from either the federal government or a state government (although as noted in the discussion of Codes in this guide, local agencies are also a source of law). The powers of the federal government are listed in the U.S. Constitution at Article I, Section 8. Those powers include, but are not limited to, immigration, bankruptcy, the postal service, intellectual property (copyright, patent, and trademark), and the military. Any powers not specifically listed in the U.S. Constitution as federal powers are left to the states. Conflicts between the laws are resolved by the Supremacy Clause of the U.S. Constitution, Article VI, which says that laws enacted in furtherance of the U.S. Constitution are the "supreme law of the land," and that federal laws have superiority over the state constitutions and laws.
Why does this matter? When you want to research a legal issue or file a lawsuit, the first thing you need to determine is whether federal or state law governs your issue. Then, you will know which sources of law to use for your research, and which court is the proper court for filing your case.
As discussed in the Codes section of this guide, each state has its own set of statutes. Most states have laws covering the following subjects, which are generally matters of state and not federal law:
Historically, federal courts heard only cases related to the interpretation of the United States Constitution and the Bill of Rights, and topics authorized by the Constitution. Federal law now controls topics such as:
Some topic areas law are governed by both state and federal law. This usually happens when Congress spends money to create programs for the general welfare. Typically when federal funds are offered to a state to participate, some element of federal law is involved.
Such areas of law include: