Here, the Supreme Court declared most of the Civil Rights Act of 1875, a "last gasp" of the radical Republicans of the Reconstruction era, unconstitutional. In particular, the Court ruled that the 14th Amendment prohibited only government violations of civil rights, not the denial of civil rights by individuals unaided by the state. Essentially, it formally ended any attempts by Republicans to ensure the civil rights of blacks, and ushered in the mass denial of civil rights to blacks until the 1960s.
The decision that Civil Rights Acts were unconstitutional has not been formally overturned. However, most recent civil rights laws have been based on the interstate commerce clause rather than on the 14th amendment.