landmark decision
landmark decision. A judicial decision that significantly changes existing law. • Examples are Brown v. Board of Educ., 347 U.S. 483, 74 S.Ct. 686 (1954) (holding that segregation in public schools violates the Equal Protection Clause), and Palsgraf v. Long Island R.R., 162 N.E. 99 (N.Y. 1928) (establishing that a defendant’s duty in a negligence action is limited to plaintiffs within the apparent zone of danger — that is, plaintiffs to whom damage could be reasonably foreseen). — Also termed landmark case. Cf. LEADING CASE.