The pivotal document that established the framework of the United States government in 1787 is the U.S. Constitution. Drafted during the Philadelphia Convention, this foundational document outlined the structure, powers, and responsibilities of the government, as well as the rights of the states and citizens. The Constitution also created a system of checks and balances among the three branches of government: legislative, executive, and judicial. Ratified in 1788, it replaced the Articles of Confederation, instituting a stronger federal government and providing for amendments that allow for the evolving interpretation of civil rights and liberty.