Dred Scott v. Sandford, 60 U.S. 393, was a landmark 1857 Supreme Court case that further polarized the United States over the issue of slavery.
The argument
Dred Scott (1799-1858) was a slave in Missouri and from 1833 to 1843, he traveled with his master, John F. A. Sanford, to the free state of Illinois and the Louisiana territory. Returning to Missouri, Scott sued Sanford, arguing that he was made a free man as he was residing in areas declared free according to the Missouri Compromise of 1820. The claim was therefore narrow and technical, turning on the effect of residence, and it relied on the settlement that had divided the country into free and slave territory rather than on any general argument against slavery itself. After a 7-2 decision announced in 1857, the Supreme Court held that African Americans were not, and never were, citizens of the United States according to the Constitution. Therefore, Scott did not have standing to sue in a federal court. The Court thus disposed of the case on a ground far wider than the question put to it: instead of deciding whether this man's residence had made him free, it decided that nobody in his position could bring such a question to a federal court at all. Furthermore, the majority held that slaves were property under the Fifth Amendment, and that any law that would deprive a slave owner's property is unconstitutional. This second holding reached well beyond the parties. If slaves were property protected by the Constitution, then the compromises confining slavery to particular territories were themselves invalid, and the political settlement by which the question had been contained fell away. The case caused an uproar and resulted in a further polarized national debate over slavery. That is the argument's connection to the war. The dispute had been managed for decades through legislative bargains about where slavery could exist, and a ruling that removed the constitutional basis for such bargains left no route by which the disagreement could be settled short of confrontation.
Premises
Counter-arguments
The Supreme Court's ruling was based on the standard of precedent while the debate over slavery had already been ongoing.
Rejecting the premises
[Rejecting P1] Accurate, though it understates what made the case consequential. The Court did not stop at standing: it struck down the Missouri Compromise's restriction on slavery in the territories, and that is the holding with political effect. [Rejecting P2] The ruling was not an application of settled precedent, which is what the counter-argument's defence requires. Freedom suits of this kind had succeeded in Missouri courts for decades before the state reversed course, and the citizenship holding went well beyond what deciding the case required — two justices dissented at length on exactly that ground. [Rejecting P3] Deepening a polarisation is not the same as causing a war, and the premise names one input among many. The sectional conflict was already far advanced, through the Compromise of 1850, the Fugitive Slave Act, Kansas–Nebraska and the violence in Kansas. The mechanism by which the decision contributed is also more specific than "uproar": by closing off the territorial compromise route, it made the dispute unresolvable through legislation and helped consolidate the party that won in 1860.