Legal Definitions - supreme law of the land

The term "supreme law of the land" refers to the highest legal authority in the United States. It establishes a hierarchy of laws, meaning that certain federal laws and agreements take precedence over state and local laws when there is a conflict. This fundamental principle ensures uniformity and consistency across the nation and is rooted in the Supremacy Clause of the U.S. Constitution.

Specifically, the "supreme law of the land" includes:

• The U.S. Constitution itself, which is the foundational document outlining the structure of government and the rights of individuals.
• Federal laws (Acts of Congress) that are passed in a way that is consistent with the U.S. Constitution.
• Treaties that the United States has entered into with other countries, once they have been ratified according to constitutional procedures.

Here are some examples illustrating how the "supreme law of the land" operates:

• Example 1: Conflict Between a State Law and the U.S. Constitution

  Imagine a state passes a law that prohibits individuals from assembling in groups of more than five people in public places, claiming it's necessary for public safety. However, the First Amendment of the U.S. Constitution guarantees the right of the people peaceably to assemble. In this scenario, the state law would be challenged in court. Because the U.S. Constitution, including the First Amendment, is the supreme law of the land, the state law would be declared unconstitutional and unenforceable, as it directly violates a fundamental right protected by the Constitution.

• Example 2: Conflict Between a State Law and a Federal Statute

  Suppose Congress passes a federal law establishing strict national standards for vehicle emissions to combat air pollution. A particular state then enacts its own law that sets much weaker emission standards for vehicles registered within its borders. When a car manufacturer tries to sell vehicles that meet only the state's weaker standards, a conflict arises. The federal law, passed by Congress within its constitutional authority (e.g., to regulate interstate commerce and promote general welfare), is the supreme law of the land. Therefore, the federal emission standards would override the state's weaker standards, and all vehicles sold in that state would be required to meet the more stringent federal requirements.

• Example 3: Conflict Between a State Law and a U.S. Treaty

  Consider a situation where the U.S. government ratifies a treaty with several other nations that guarantees the protection of certain endangered species, including specific habitats that cannot be disturbed. Later, a state passes a law allowing for extensive commercial logging in one of these protected habitats, arguing it will boost the local economy. This creates a direct conflict between the state law and the international treaty. Since the treaty, once ratified by the U.S., becomes part of the supreme law of the land, the state law permitting logging in the protected habitat would be deemed invalid because it conflicts with the obligations the U.S. has undertaken through the federal treaty.