Final answer:
Dred Scott was the escaped slave involved in the decision later overturned by Plessy v. Ferguson.
Step-by-step explanation:
The escaped slave who was involved in the decision later overturned by Plessy v. Ferguson was Dred Scott. The Supreme Court ruled in the Dred Scott v. Sandford case that he, as an African American, was not a citizen and therefore could not sue. This decision further entrenched the institution of slavery and denied rights to enslaved people.
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