'The legal system in the United States is an often-uneasy balance of national government and the governments of the fifty states. There are parallel systems of executive, legislative and judicial branches of government, and shared powers among the states and the federal governments.'
Read more about the U.S. Legal System and free sources of Law at A Guide to the U. S. Federal Legal System Web-based Public Accessible Sources (July/August 2018, Globalex)
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Federal
The United States Code (USC) is freely available online via:
The United State Code Annotated is available online via:
Session Laws (Public and Private Laws) are freely available online via:
State
State codes are freely available online via:
Information on the Federal court system can be found online:
Authorised Reports
Historical case law