CaseTrail

Landmark Supreme Court decisions

“Landmark” means different things to different people. CaseTrail uses two objective tests from the Supreme Court Database: decisions that formally altered the Court’s own precedent, and decisions that held a law unconstitutional. Many famous cases meet one of these tests; some important cases meet neither.

198altered precedent
126struck an act of Congress
485struck a state law
65struck a local ordinance

Altered precedentActs of CongressState lawsLocal ordinances

Decisions that altered precedent (198)

Acts of Congress held unconstitutional (126)

State laws held unconstitutional (485)

Local ordinances held unconstitutional (65)

Source: Supreme Court Database, 2026 Release 01 (data file dated September 8, 2026). Imported into CaseTrail November 5, 2026. Coverage: decisions from the 1946 through 2025 Terms. Methodology · Report an error