Book excerpt: The Supreme Court's 1857 Dred Scott decision denied citizenship to African Americans and enabled slavery's westward expansion. It has long stood as a grievous instance of justice perverted by sectional politics. Austin Allen finds that the outcome of Dred Scott hinged not on a single issue-slavery-but on a web of assumptions, agendas, and commitments held collectively and individually by Chief Justice Roger B. Taney and his colleagues. By showing us the political, professional, ideological, and institutional contexts in which the Taney Court worked, Allen reveals that Dred Scott was not simply a victory for the court's prosouthern faction. It was instead an outgrowth of Jacksonian jurisprudence, an intellectual system that charged the court with protecting slavery, preserving both federal power and state sovereignty, promoting economic development, and securing the legal foundations of an emerging corporate order-all at the same time.