Which document outlines the fundamental laws of the United States?

The Constitution serves as the foundational legal document for the United States, establishing the framework for the government and outlining the fundamental laws by which the country operates. It sets forth the principles of American democracy, including the separation of powers, checks and balances, and the rights of citizens. Each section of the Constitution addresses different aspects of governance and individual rights, making it a comprehensive guide to the country's legislative, executive, and judicial branches.

In contrast, the Declaration of Independence, while a pivotal document in asserting the colonies' separation from British rule and articulating the principles of liberty and equality, does not function as a governing document. The Federalist Papers are a collection of writings intended to promote the ratification of the Constitution and provide insight into its interpretation but are not legal documents themselves. The Articles of Confederation served as the first governing document of the United States but were ultimately replaced by the Constitution due to their weaknesses, which highlighted the need for a stronger federal government.