Brown v. Plata, 563 U.S. 493 (2011), was a decision by the Supreme Court of the United States holding that a court-mandated population limit was necessary to remedy a violation of prisoners’ Eighth Amendment constitutional rights. Justice Kennedy filed the majority opinion of the 5 to 4 decision, affirming a decision by a three judge panel of the United States District Court for the Eastern and Northern Districts of California which had ordered California to reduce its prison population to 137.5% of design capacity within two years.