Law
The Use of Foreign Law in Constitutional Interpretation
Quick fact
In Roper v. Simmons (2005), the U.S. Supreme Court cited international consensus against the death penalty for juveniles, drawing on foreign laws that, in some cases, had already been repealed—yet the Court still used them to support its interpretation of the Eighth Amendment.
Why this is interesting
In 2005, the U.S. Supreme Court cited a foreign law that was not even in force in its own country—and the decision sparked a firestorm. Why would a judge look to another nation's laws to interpret their own constitution?
Read the full explanation
Understanding The Use of Foreign Law in Constitutional Interpretation
Think of a constitution as a nation's foundational rulebook. When a judge interprets a vague clause, such as 'cruel and unusual punishment,' they might ask what 'cruel' meant in 1791. But some judges also ask: 'How have other modern democracies interpreted similar rights?' This is the practice of using foreign law. It does not bind the judge—it is not like a precedent from a higher court. Instead, foreign law acts as a persuasive comparison, a way to see how other societies have solved similar problems. For example, in deciding whether a punishment is 'cruel,' a judge might note that virtually every other Western democracy has abolished the death penalty for minors. That observation doesn't command the result, but it informs the judge's sense of evolving standards of decency. The key is that foreign law is consulted as a source of wisdom, not as a source of authority.
A deeper explanation
The use of foreign law is a subset of 'judicial dialogue'—the ongoing conversation among courts worldwide. Underlying it are two competing philosophies. On one side, 'originalists' argue that the Constitution's meaning was fixed at ratification, so foreign law from 21st-century democracies is irrelevant and potentially subversive; it could import values the framers never intended. On the other side, proponents of a 'living constitution' see the document's broad phrases—like 'due process' or 'equal protection'—as inviting modern interpretation. They argue that foreign law offers valuable empirical and moral data, helping judges identify universal human rights norms and avoid parochialism. The practice is not new: the Supreme Court has cited foreign law since the early 19th century, but it became highly politicized after decisions like Roper. Critics also worry about 'cherry-picking'—judges might select only foreign laws that support their preferred outcome. Defenders counter that judges use foreign law judiciously, often in cases where international consensus itself is the evidence, as in Eighth Amendment analyses. The legitimacy of the practice hinges on whether one views the Constitution as a self-contained social contract or as part of an evolving global human-rights tradition.