The legal system contains and regulates citizens' behavior and permits the smooth functioning of a civil society. In the United States, according to the official website of the White House, the federal courts have the sole power of determining the constitutionality of laws and issuing rulings relating to their implementation.
The legal system in the United States is defined by the Constitution. As described by Whitehouse.gov, Section III of the Constitution establishes a Supreme Court that holds jurisdiction over lower courts. These courts review laws that have been passed by legislatures and issue rulings that determine the laws' effects on the way citizens live. One example of how the legal system operates is in the realm of criminal law. The legal system of the courts protects the rights of the accused and provides a framework for determining the truth of accusations. Sometimes, the courts rule that a law is partly or wholly unconstitutional, which results in the repeal of the offending law.
Another purpose of the legal system is to balance state power against federal authority. According to USLegal, Congress is not always at liberty to pass legislation that is properly the concern of the respective states. In this case, the U.S. legal system provides reasonable boundaries for the just exercise of power on federal, state and local levels.