Final answer:
The Supreme Court ruled in the Dred Scott v. Sandford case that slaves who escaped must be returned to their owners. The ruling upheld the rights of slave owners and declared that slaves were property, not citizens. The Supreme Court also ruled that Congress had no authority to stop or limit the spread of slavery into American territories.
Step-by-step explanation:
In 1857, the Supreme Court ruled in the Dred Scott v. Sandford case that slaves who escaped must be returned to their owners. This ruling was significant because it upheld the rights of slave owners and declared that slaves were property, not citizens, and therefore had no legal rights. The Supreme Court also ruled that Congress had no authority to stop or limit the spread of slavery into American territories, making the Missouri Compromise unconstitutional.
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