What the Judicial Branch Does

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The Supreme Court ruled in 1954 that state-sanctioned racial segregation in public schools was unconstitutional. The judicial branch decides legal disputes by applying the law, including the Constitution, even when that means rejecting a policy the government has approved.

Federal courts exercise this power through a genuine dispute between opposing parties, rather than a hypothetical question. That gives judges a way to check what government does without a general mandate to choose its policies.

Courts decide what the law means in a dispute

The federal judiciary is the federal court system, with the Supreme Court and the lower courts Congress establishes under Article III of the Constitution. “Judicial” describes the work courts do; “judiciary” names the courts that do it. Congress passes federal laws, the president signs them, and courts resolve federal-law cases and decide whether federal laws are constitutional. The executive branch carries out and enforces federal laws through the president and federal departments and agencies. Judges depend on the executive branch to enforce their decisions.

In a federal civil case, two or more parties have a legal dispute, and the plaintiff begins the case by filing a complaint. The plaintiff may ask for money for harm, an order stopping harmful conduct, or a declaration of legal rights. A court’s work is therefore broader than announcing whether someone broke a criminal law.

In the federal system, only the government starts a criminal case, usually through the prosecutors of a U.S. attorney’s office working with a law enforcement agency. A U.S. attorney’s office represents the United States in federal-law cases, while state or local prosecutors represent the state in cases arising under state law.

At trial, the government must prove guilt beyond a reasonable doubt; the defendant does not have to prove innocence. That standard means the evidence must be so strong that there is no reasonable doubt the defendant committed the crime. The government’s responsibility to prove its accusation puts a limit on its power to punish.

The dispute has to belong in the court

The Constitution divides power between the federal government and state governments, which have their own court systems. State courts handle most criminal cases and most disputes involving contracts, personal injuries, family matters, and probate, the handling of a deceased person’s estate. Federal courts hear cases involving the Constitution and federal laws, as well as matters such as treaties, disputes between states, and bankruptcy. Bankruptcy cases go to federal bankruptcy courts, which help people and businesses that cannot pay their debts get what the courts call a “fresh start.”

State courts also interpret federal law and the U.S. Constitution, and those interpretations may be appealed to the Supreme Court.

A dispute’s seriousness does not by itself make it a federal case; the subject and the court’s legal authority matter. The Constitution sets the outer limits of federal jurisdiction, a court’s authority to decide a case, but federal courts can exercise only the jurisdiction Congress grants them.

A plaintiff who wants a federal court to decide a legal question must show an injury suffered or likely to be suffered, that the defendant likely caused it, and that the relief requested would likely remedy it. This requirement, called standing, connects the legal question to the person asking the court to answer it. A general legal, moral, ideological, or policy objection to government action does not by itself establish standing.

Trials establish facts; appeals examine the decision

U.S. district courts are federal trial courts that resolve disputes by determining facts and applying the law to them. In a jury trial, the judge explains the applicable law, and jurors weigh the evidence, decide the facts, and apply that law to the facts. In a civil trial without a jury, the judge decides the factual issues and the relief to award.

Federal courts of appeals review district-court procedures and decisions to determine whether proceedings were fair and the law was applied correctly. Appeals courts do not retry cases, hear new evidence or witness testimony, or use a jury.

An appellate panel issues a decision, usually with an opinion explaining its reasoning, and may send the case back to the trial court for additional proceedings. Sending the case back is called a remand. In a criminal case, the defendant may appeal a guilty verdict, but the government may not appeal a not-guilty verdict. Either side may appeal the sentence imposed after a guilty verdict.

The Supreme Court decides which disputes merit its review

Certain cases, such as suits between states, begin in the Supreme Court itself under what is called its original jurisdiction. Its appellate jurisdiction, the power to hear a case on appeal from another court, covers almost any other case that involves a point of constitutional or federal law. A party seeking that review files a petition for a writ of certiorari, a request for the justices to review a case heard in a lower court. Granting it is a matter of the Court’s discretion, not a right. Four justices must vote to grant a certiorari petition, a practice known as the Rule of Four.

The Supreme Court’s Rule 10 identifies important conflicts over federal law and important unsettled federal questions as reasons that can support review. A petition is rarely granted merely for an erroneous factual finding or the misapplication of a correctly stated rule of law. The selection process steers the Court toward questions that matter beyond one losing party’s objection.

Most federal courts of appeals decisions are final, and they bind lower courts within the same circuit, the region those courts serve. A case need not reach the Supreme Court for an appellate decision to shape how lower courts decide later disputes.

Judicial review can stop unconstitutional government action

Judicial review is the power of courts, including the Supreme Court, to decide whether legislative or executive action violates the Constitution. An unconstitutional act conflicts with the Constitution, rather than simply being unpopular or unwise. In Marbury v. Madison in 1803, the Supreme Court held that an act of Congress contrary to the Constitution could not stand.

Outgoing President John Adams had appointed William Marbury as a justice of the peace, but Secretary of State James Madison refused to deliver his commission. Marbury asked the Supreme Court to order Madison to deliver his commission. The Court refused to apply the Judiciary Act of 1789 provision that gave it original jurisdiction, the power to hear a case first, over requests for orders compelling government officials to act. The Court said the Constitution did not permit it to have original jurisdiction in that matter. The foundational example of judicial review was therefore also a limit on the Supreme Court’s own authority: Congress could not enlarge the Court’s original jurisdiction by passing a law inconsistent with the Constitution.

On May 17, 1954, the Supreme Court ruled in Brown v. Board of Education of Topeka, Kansas that state-sanctioned public-school segregation violated the Fourteenth Amendment. The decision rejected the separate-but-equal doctrine in public education, a precedent the Supreme Court had set nearly 60 years earlier in Plessy v. Ferguson. It shows that precedent, an earlier decision that guides later cases, carries weight without being permanent.

Judges have independence, and limits on their power

The president nominates Supreme Court justices and federal circuit and district judges, and the Senate confirms them. Article III gives these judges lifetime appointments, except in very limited circumstances. Their salaries cannot be reduced while they remain in office. Elected officials choose the judges, but tenure and salary protections shield a judge, once appointed, from pressure over a particular decision.

Article III judges can be removed from office only through impeachment by the House of Representatives and conviction by the Senate. Congress checks the courts in another way as well: it establishes the lower courts and grants the jurisdiction they can exercise.

The political-question doctrine is a narrow exception to judicial decision-making: it covers an issue that the Constitution assigns to another branch, or one for which courts lack workable legal standards. Courts cannot avoid their responsibility to decide a legal dispute merely because its issues have political implications.

How to follow a case or watch a proceeding

Public Access to Court Electronic Records, known as PACER, lets account holders find federal appellate, district, and bankruptcy case and docket information online. PACER charges ten cents per page, with a three-dollar cap for a docket, motion, order, judgment or brief. That cap does not apply to search results, reports that are not case-specific, or transcripts. Fees are waived if your charges total thirty dollars or less in a quarter. Effective January 1, 2027, the per-page fee rises to twelve cents for five years, and the quarterly fee-waiver threshold rises to forty dollars.

Case information is also available through the clerk’s office at the courthouse where the case was filed. Most federal courtroom proceedings are open to the public, although space and security needs can limit access. To watch a proceeding, check the local federal court’s calendar online or at the courthouse.