The Constitution's words are often broad: due process, equal protection, unreasonable searches, cruel and unusual punishments. Judges must decide what those words mean in cases the framers never imagined. Different methods of interpretation can lead to sharply different answers, and since the 1980s the choice of method has become central to how Presidents select judges and how senators evaluate them.
This guide explains the major approaches, how they work in practice, and the arguments for and against each.
Judicial restraint, associated with Justices Oliver Wendell Holmes and Felix Frankfurter, urges courts to defer to elected branches unless a violation is clear. Holmes famously dissented in Lochner v. New York in 1905, when the Court struck down a labor law in the name of economic liberty. Judicial activism has no fixed definition and is usually a criticism of decisions that strike down laws or create new rules, a charge leveled at liberal rulings of the Warren Court and at conservative rulings of recent decades. Many scholars now distinguish between methods of interpretation and willingness to overturn laws.
Supporters of originalism and textualism say they offer neutral, predictable rules that keep judges from making policy and leave change to voters and legislatures. Critics say historical evidence is often ambiguous, that judges can select history to reach preferred results, and that originalism freezes a Constitution written when many Americans were excluded. Supporters of living constitutionalism say it lets the law protect rights in new circumstances, while critics say it has no clear limits. Other scholars propose alternatives, from common good constitutionalism to approaches emphasizing democratic participation, and many judges blend several methods.
Textualism applies to statutes the principle that the enacted words are the law. Textualists rely on ordinary meaning, dictionaries, grammar, and canons of construction, and they are skeptical of legislative history such as committee reports, which they say is not voted on and can be manipulated. The approach now dominates statutory interpretation at the Supreme Court, though justices often disagree about what the text means, as in cases that split self-described textualists. Critics say textualism can ignore a law's evident purpose and produce results Congress did not intend.
Originalists argue that the Constitution's meaning was fixed at ratification and that judges should apply that meaning until it is changed by amendment. Early versions focused on the framers' intentions, but most originalists now look to the original public meaning, how a reasonable reader at the time would have understood the words. The approach gained prominence in the 1980s through Attorney General Edwin Meese, Judge Robert Bork, and Justice Antonin Scalia. Originalists say it constrains judges and respects democracy, since the people can amend the Constitution through Article V.
Stare decisis, the principle of standing by prior decisions, gives the law stability, but the Court has overruled its own precedents more than 140 times. Recent examples include Dobbs v. Jackson Women's Health Organization in 2022, which overruled Roe v. Wade, Loper Bright in 2024, which overruled Chevron, and Trump v. Slaughter in 2026, which overruled Humphrey's Executor. In New York State Rifle and Pistol Association v. Bruen in 2022, the Court adopted a test asking whether gun laws are consistent with the nation's historical tradition, which it refined in United States v. Rahimi in 2024, increasing the role of history in constitutional cases.
Living constitutionalists argue that the Constitution's broad language was meant to endure and must be applied to changing conditions, drawing on precedent, evolving values, and principles such as equality and liberty. Justice William Brennan was a leading advocate, and supporters point to Brown v. Board of Education, which rejected the reasoning of Plessy v. Ferguson. Justice Stephen Breyer emphasized pragmatism, considering the purposes of laws and the real-world consequences of rulings. Critics say these approaches let judges substitute their own policy preferences for the law.
See how judges are selected in how federal judges are chosen, read the text being interpreted in the Constitution, article by article, or follow the cases that define the branches in landmark separation of powers cases.