The Government of the United States, the federal government, is divided into three branches: the executive power, invested in the President, the legislative power, given to Congress (the House of Representatives and the Senate), and the judicial power, vested in one Supreme Court and other federal courts created by Congress. The Constitution provides a system of checks and balances designed to avoid the tyranny of any one branch.
Most important actions require the participation of more than once branch of government. For example, Congress passes laws, but the President can veto them. The executive branch prosecutes persons for criminal violations, but they must be tried by the courts. The President appoints federal judges, but their appointment must be confirmed by the Senate.
Another important function of the Constitution is to divide power between the national government and the state governments. This division of authority is referred to as “federalism.” The federal government is very strong, with much power over the states, but at the same time, it is limited to the powers enumerated in the Constitution. Powers not delegated to the federal government, nor prohibited to the states are reserved to the states or to the people. Although the powers of the federal government are limited to those enumerated in the Constitution, those enumerated powers have been interpreted very broadly. And under the supremacy clause of the Constitution, federal law is supreme over state law. State or local laws that conflict with the Constitution or federal statutory law are preempted.
The Constitution also limits the powers of the states in relation to one another. Because the United States Congress has been given the power to regulate interstate commerce, the states are limited in their ability to regulate or tax such commerce between them. Under the Constitution’s privileges and immunities Clause, states are prohibited from discriminating in many ways against citizens of other states.
