In the Scott v. Sandford case, Scott’s argument was based on

Dred Scott argued that because he had lived in free territory, he should be free. The Missouri Compromise had prohibited slavery in much of that territory, so it was central to his argument. The Supreme Court later ruled the Missouri Compromise unconstitutional. The Kansas-Nebraska Act, Fugitive Slave Act, and Fourteenth Amendment were not the basis of Scott’s argument.

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