Dred Scott v. Sandford (1857)

Definition from Nolo’s Plain-English Law Dictionary

The U.S. Supreme Court decision in which the Court ruled that African Americans, whether enslaved or free, were not citizens of the United States and therefore did not have the right to sue in federal court. The Court also ruled that the federal government could not prohibit slavery in the territories. The decision was a prime factor leading to the Civil War, but was eventually rendered moot by the 14th Amendment to the U.S. Constitution -- which provides that anyone born or naturalized in the United States is a citizen of the nation and of his or her state.

Definition provided by Nolo’s Plain-English Law Dictionary.