Courts & the Legal System

Law in the United States comes from four main places:

• Constitutions. The U.S. Constitution is the highest law in the country. Each state also has its own constitution, which cannot take away rights the federal Constitution guarantees.
• Statutes. Laws passed by Congress or a state legislature, such as speed limits or minimum wage laws.
• Regulations. Detailed rules written by agencies (for example, the Food and Drug Administration) under authority a statute gave them.
• Case law. Written court decisions. Under the idea of precedent, courts generally follow earlier decisions from higher courts in the same system.

The United States runs two court systems. State courts handle the large majority of cases: traffic tickets, most crimes, family law, landlord-tenant disputes, contracts, and personal injury. Federal courts are courts of limited power. They mainly hear cases involving federal law or the Constitution, cases where the United States is a party, and "diversity" cases between citizens of different states where more than $75,000 is at stake.

Whether a court has the power to hear your case is called jurisdiction. A court needs power over the subject matter and power over the particular defendant.

A trial court is where a case starts. Witnesses testify, documents are shown, and a judge or jury decides what actually happened. An appellate court does something different: it reads the record and the written arguments and decides whether the trial court applied the law correctly. There are no new witnesses on appeal.

In the federal system the path is: U.S. District Court → U.S. Court of Appeals (a "circuit") → Supreme Court of the United States. Most state systems follow the same three-step shape. The Supreme Court hears only a small fraction of the cases it is asked to review.

A simple way to remember it: the jury decides the facts, and the judge decides the law. The jury weighs the evidence and decides who to believe. The judge runs the trial, rules on objections, explains the legal rules to the jury in instructions, and enters judgment.

Not every case gets a jury. The Sixth Amendment guarantees a jury in serious criminal cases, and the Seventh Amendment preserves jury trials in many federal civil cases, but parties can waive the jury and let a judge decide.

• Who sues. In a civil case a plaintiff sues a defendant. In a criminal case the government prosecutes the defendant.
• What is at stake. Civil cases usually end in money damages or a court order. Criminal cases can end in fines, probation, or prison.
• Standard of proof. Civil plaintiffs usually must prove their case by a "preponderance of the evidence" (more likely than not). Prosecutors must prove guilt beyond a reasonable doubt.
• Both can happen. The same conduct can lead to a criminal prosecution and a separate civil lawsuit, because the standards and the parties are different.