On March 6, 1857, a divided Supreme Court announced its landmark Dred Scott decision. A narrow majority held that slave or free, blacks were not American citizens and therefore could not sue in American courts. Furthermore, Chief Justice Roger B. Taney, himself a former slaveholder, announced that Congress had no lawful power to prohibit slavery in federal territories. To [William Lowndes] Yancy and virtually all white southerners, this decision settled the territorial question once and for all, and in their favor; it simply stated what most had argued at least since the Missouri Compromise in 1820. To northerners, Republicans in particular, the case struck at the heart of their values and their party creed. James Buchanan stood foursquare behind the decision, earning him praise and respect from white southerners and suspicion and ignominy from fellow northerners.