Final answer:
Chief Justice Taney was referring to the Missouri Compromise of 1820 and the Northwest Ordinance of 1787.
Step-by-step explanation:
Chief Justice Taney was specifically referring to the Missouri Compromise of 1820 and the Northwest Ordinance of 1787 when he made his decision in the Dred Scott Case.
In the case, Dred Scott, an enslaved person, claimed his time living in free territories made him free. The Supreme Court declared that the relevant parts of the Missouri Compromise were unconstitutional, ruling that Scott remained enslaved. This decision also had implications for the Northwest Ordinance, which had prohibited slavery in certain territories.
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