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The judicial branch: lesson overview

A high-level overview of the judicial branch and its power of judicial review.
The design of the judicial branch protects the Supreme Court’s independence as a branch of government. The Supreme Court wields the power of judicial review to check the actions of the other branches of government.

Key terms

inferior courtsAlso called lower courts, inferior courts include all US federal courts below the Supreme Court, including courts of appeals, district courts, and federal tribunals. Congress retains the power to establish inferior courts and to determine how they operate.
John MarshallAn early, influential Chief Justice of the United States who led the Supreme Court from 1801-1835. Marshall wrote several foundational Court decisions, including Marbury v. Madison and McCulloch v. Maryland, which enhanced the power of the judicial branch and affirmed the supremacy of federal law over state law.
judicial independenceFactors that prevent members of the legislative and executive branches from influencing Supreme Court justices, including lifetime appointments for justices and a ban on salary decreases for sitting justices.
judicial reviewThe Supreme Court’s power to review whether acts of the legislative branch, the executive branch, and state governments are consistent with the Constitution, and to strike down acts it finds unconstitutional.
Supreme CourtThe highest federal court of the United States, established by Article III of the US Constitution, with nine sitting justices today. Unlike inferior courts, the Supreme Court is shielded from the influence of Congress, which cannot change its jurisdiction or the salaries of sitting justices.

Documents and cases to know

Federalist no. 78 (1788) - “The Judiciary Department,” written by Alexander Hamilton. In this essay advocating for the ratification of the US Constitution, Hamilton describes the proposed form for the new government’s judicial branch. He argues that judges should serve for life pending good behavior to ensure judicial independence, and that the judicial branch will be the “least dangerous” branch of government since it can neither wage war nor collect taxes. Hamilton also provides an early argument for the power of judicial review, stating that the courts’ duty is “to declare all acts contrary to . . . the Constitution void.”
Article III - Article III of the US Constitution establishes the judicial branch of US government. It explicitly creates one Supreme Court, but gives Congress the power to create all other inferior courts. Article III guarantees judicial independence by granting lifetime appointments for justices and preventing Congress from lowering the salaries of sitting justices.
Marbury v. Madison (1803) — An early Supreme Court case that affirmed the Court’s power of judicial review by striking down a law made by Congress as unconstitutional. In his written opinion, Chief Justice John Marshall declared that “an act of the legislature repugnant to the Constitution is void.”

Key takeaways

Constitutionalism - The federal courts use judicial review to determine whether the acts of Congress, the executive branch, and state governments comply with the Constitution. This exemplifies the principle of checks and balances by ensuring that the other branches of government cannot act outside the bounds of the Constitution without consequence.
The judicial branch also demonstrates the importance of separation of powers, as lifetime appointments for justices and bans on salary decreases for sitting justices ensure the judicial branch’s independence from the interference of the other two branches.

Review questions

What is judicial review? Can you explain it in your own words?
Did the Framers intend for the Supreme Court to have the power of judicial review? How do we know?
Do you agree with Hamilton’s belief that the judicial branch is the “least dangerous” branch of government? Why or why not?

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