Dred Scott was a slave owned by John Emerson, an army surgeon from the slave state of Missouri. Emerson took Scott with him when he moved to the free state of Illinois in 1834, and to the free Territory of Wisconsin in 1836.
Emerson died in 1843 and his widow, Irene, inherited Scott and his wife and child. Scott later attempted to buy his family’s freedom by offering Irene $300 but she refused. In response the Scotts sued for freedom, with legal advisors arguing that their residence in a free state and a free territory meant they must have been emancipated.
Drawing on the Missouri precedent of “once free, always free” the case was not fully heard until 1850. Although the jury ruled in Scott’s favour, the Missouri Supreme Court reversed the decision after Irene Emerson appealed. She then transferred the Scotts to her brother, John F. A. Sanford, in New York.
In 1853 the case went to the Federal Courts, which found in Sanford’s favour. Scott subsequently appealed this ruling to the Supreme Court, which mis-spelled Sanford’s name due to a clerical error and didn’t deliver the majority opinion until 6 March 1857.
Chief Justice Roger B. Taney wrote the decision, which said that black people could never be citizens of the United States and so did not have right to bring a case to the Federal Courts. Furthermore, the decision stated that Congress did not have the right to regulate slavery in the territories meaning that, as private property, slaves could not be taken away from their owners. The decision increased tensions within the United States and contributed to both the election of Abraham Lincoln and the outbreak of Civil War.