The law followed the Selma to Montgomery marches, including Bloody Sunday on March 7, 1965, when Alabama troopers beat marchers on the Edmund Pettus Bridge. Section 5 required covered states and counties, identified by a formula in Section 4(b), to clear voting changes with the Justice Department or a federal court. Section 2 bans voting practices that discriminate by race nationwide. In Mississippi, Black voter registration rose from about 7 percent in 1964 to about 60 percent in 1967.
Courts have since narrowed the law. In Shelby County v. Holder in 2013, the Supreme Court struck down the Section 4(b) formula, which ended preclearance. Many formerly covered states then closed polling places, purged voter rolls and passed new ID laws.
On April 29, 2026, in Louisiana v. Callais, the Supreme Court ruled 6 to 3 that Section 2 is violated only with strong evidence of intentional discrimination. That makes it much harder to challenge district maps that dilute Black and Latino votes.