By 1850 the technical issues involving the Scotts’ status as slaves had been overshadowed by a larger national controversy concerning the nature of citizenship in the United States and the authority of the federal government over slavery in the territories. Advocates of Southern Rights in the federal congress, led by the aged but obdurate senator from South Carolina, John C. Calhoun, vigorously defended the rights of slave holders to carry their property into the territories and issued a manifesto to this effect popularly known as the "Southern Address" (1849). In the "Jackson Resolutions" (1849), proslavery Missourians led by future governor Claiborne Fox Jackson, directed their state’s representatives in congress -- most pointedly the now antislavery senator Thomas Hart Benton -- to support Calhoun’s doctrines. Judge William B. Napton, one of the three justices on the Missouri Supreme Court, drafted the Jackson Resolutions at the behest of Claiborne Jackson and recorded in his diary that he intended to use the Dred Scott case to bring the principles of the Southern Address to bear on Missouri law.

Notwithstanding Judge Napton’s intentions it seemed to many that the Scotts had a good chance of winning their freedom. Precedent favored them. In a case similar to theirs, Rachel v. Walker (1836), the Missouri Supreme Court had ruled that a slave owned by an army officer had been made free while residing in the Wisconsin Territory. Moreover, in a U.S. Supreme Court case, Strader v. Graham (1851), Chief Justice Roger B. Taney, writing for the majority, ruled that the law of the state in which a slave’s suit was tried would determine the case’s outcome. This ruling seemed to indicate that the precedent established in Rachel v. Walker would prevail and that the Scotts would be freed. But there was another dimension to the Strader decision that encouraged Judge Napton and his successors to arrive at a very different conclusion in Scott v. Emerson (1852).

At issue in Strader and in the Dred Scott case was a question of conflicts of law -- that is, when the law of one state conflicts with the law of another (as was the case in issues relating to slavery), judges needed to decide which law should prevail. In efforts to defend fugitive slaves, antislavery reformers frequently invoked this principle to argue that the law of slavery could not extend into a free state. Moving in the opposite direction on the slavery issue the Missouri Supreme Court used the Strader decision to overturn Rachel v. Walker and assert proslavery views. Although voters turned Judge Napton out of office, a proslavery majority on the court prevailed and the Missouri high court followed the course initiated by Judged Napton to rule ruled that a slave in a slave state did not become free by residing in a state or territory which did not recognize slavery. Two of the judges joined in a majority decision to hold that the laws governing the free states and territories had no effect in Missouri. Meeting in the Courthouse in St. Louis in October 1851, the Missouri Supreme Court ruled that Strader required that positive slave law in Missouri governed the case and that the Scotts remained slaves.