How does a author develop the central idea of the section The Great Divide

What policy did "jim crow" laws put in place? black codes integration segregation 2. the supreme court case that established the doctrine of "separate but equal" was dred scott v. sandford plessy v. ferguson brown v. board of education 3. the supreme court case that overturned the doctrine of "separate but equal" wasdred scott v. sandford plessy v. ferguson brown v. board of education