Judicial review is the power of courts to decide whether a government action is lawful. In the United States, that usually means asking whether a statute, regulation, executive action, state law, criminal procedure, or official decision is consistent with the Constitution and with valid laws passed by Congress.

Courts do not issue general advice about whether a policy is wise. A real case must be brought by real parties with a legal injury before judicial review begins. That requirement matters because federal courts are supposed to decide cases and controversies, not write advisory opinions or supervise politics in the abstract.

When a court finds a conflict between a government action and higher law, it can refuse to enforce that action in the case before it, block it through an injunction, reverse a lower court decision, or send the matter back for further proceedings.

The Constitution gives federal courts “the judicial power,” but it does not use the exact phrase “judicial review.” The doctrine became central after Marbury v. Madison in 1803, when Justice is a federal court term connected to federal court structure; it helps explain who is involved, what step is happening, and what legal effect the step may have.">Chief Justice John Marshall explained that courts must apply the Constitution when it conflicts with an ordinary statute.

In Marbury, William Marbury asked the Supreme Court to order Secretary of State James Madison to deliver a judicial commission. The Court concluded that part of the law Marbury relied on gave the Court more original jurisdiction than Article III allowed. Marbury lost, but the decision established the principle that a federal court may decline to enforce a law that conflicts with the Constitution.

Later cases extended the idea. Martin v. Hunter’s Lessee and Cohens v. Virginia confirmed Supreme Court review of state-court judgments involving federal law. United States v. Nixon showed that judicial review can reach presidential claims of power. Modern administrative-law cases show that courts also review whether agencies acted within statutory authority and followed required procedures.

Judicial review usually unfolds through ordinary litigation. A person, business, state, organization, or government official claims that a law or action has harmed them. A court first checks jurisdiction, standing, timing, and other threshold issues. If the case can proceed, the court reviews the law, facts, record, and arguments.

Most cases begin in a trial court. If a party appeals, an appellate court reviews the legal reasoning below. The Supreme Court hears only a small fraction of cases, usually after granting certiorari. A decision can resolve the parties’ dispute and also become precedent that guides later courts.

The path matters because judicial review is not just a theory of government. It is a process: complaint, briefing, record, argument, decision, remedy, and sometimes appeal.

Judicial review can apply to several kinds of government action. Courts may review acts of Congress, state laws, local ordinances, executive orders, agency regulations, enforcement actions, criminal procedures, and lower-court rulings. In each setting, the question is not simply whether the judge likes the policy. The question is whether the government had lawful authority and followed legal limits.

For statutes, courts ask whether Congress or a state legislature had constitutional power and whether the law violates rights. For executive and agency action, courts ask whether officials stayed within statutory authority, followed required procedures, and respected constitutional limits. For state action, courts may apply the Constitution and valid federal laws through the Supremacy Clause.

Judicial review has limits. Federal courts generally do not decide abstract questions, political disagreements with no legal injury, cases filed too early, cases that are already resolved, or disputes outside the court’s jurisdiction. These limits help keep courts from becoming general policy councils.

Some disputes are dismissed because the plaintiff lacks standing. Others are not ripe because the alleged injury has not happened yet. Some become moot because the controversy has ended. A court may also refuse to decide certain political questions that the Constitution commits to the elected branches or that lack manageable legal standards.

These doctrines can be frustrating because they sometimes prevent courts from answering important questions. But they also protect the separation of powers by limiting courts to disputes they are institutionally suited to decide.

Courts do not apply the same level of scrutiny to every law. Many economic and ordinary regulatory laws receive rational basis review, a deferential standard that asks whether the law is rationally related to a legitimate government purpose. Some classifications, such as sex-based classifications, may receive intermediate scrutiny. Laws that burden fundamental rights or use certain suspect classifications can trigger strict scrutiny, the most demanding standard.

In administrative cases, courts may also ask whether an agency acted arbitrarily or capriciously, whether it followed required procedures, and whether it correctly interpreted the statute Congress gave it. After Loper Bright Enterprises v. Raimondo, courts no longer defer to an agency’s interpretation of an ambiguous statute under the old Chevron deference framework.

Judicial review is easiest to understand through cases. Marbury v. Madison established the doctrine. Brown v. Board of Education used judicial review to reject state-mandated school segregation. United States v. Nixon limited presidential claims of executive privilege. Youngstown Sheet & Tube Co. v. Sawyer rejected a presidential seizure of steel mills without congressional authorization.

Modern cases continue to shape the field. Citizens United v. FEC reviewed campaign-finance restrictions under the Amendment is a civic and constitutional law term used to understand government power, rights, or public process.">First Amendment. Dobbs v. Jackson Women’s Health Organization showed that constitutional precedent can be overturned. Loper Bright changed how courts review agency interpretations of federal law. Together, these cases show that judicial review can protect rights, limit government power, reshape public policy, and generate deep public disagreement.

Supporters argue that judicial review is essential because it keeps government inside constitutional limits and gives individuals a legal path to challenge unlawful action. Without judicial review, constitutional rights could depend entirely on whether Congress, the President, state officials, or agencies choose to respect them.

Critics argue that judicial review can give unelected judges too much power over decisions made by elected officials. This concern is sometimes called the countermajoritarian difficulty: courts can overturn laws passed by representatives who answer to voters. The debate is not whether courts should follow the Constitution, but how aggressively they should use judicial power and how much deference they should give to elected branches and agencies.

This debate also connects to methods of constitutional interpretation. Originalism, textualism, living constitutionalism, judicial restraint, and judicial activism are not just academic labels. They often shape how judges understand constitutional text, precedent, rights, and government power.

Visitors who want to go deeper should read primary sources and reliable court resources. Supreme Court opinions, Library of Congress resource that provides legal analysis and interpretation of the United States Constitution.">Constitution Annotated, federal court explainers, and case archives help connect this plain-language overview to the legal materials courts actually use.

The most useful next step is to read one landmark case slowly: start with the facts, then the legal question, the holding, the reasoning, and the practical impact. Once those pieces are clear, judicial review becomes less like an abstract phrase and more like a working tool of constitutional government.