I know that the Dred Scott case was a landmark Supreme Court decision in 1857 that ruled that African Americans, whether enslaved or free, were not considered citizens and therefore had no standing to sue in federal court. The decision also declared the Missouri Compromise unconstitutional and stated that Congress had no right to prohibit slavery in the territories. The ruling was seen as a victory for supporters of slavery, while abolitionists and opponents of slavery were outraged by the decision.
