In the Plessy v. Ferguson case, the Supreme Court ended up ruling in favor of Ferguson. Plessy's arguments based on the fact that Louisiana law conflicted with the thirteenth and fourteenth amendment rights, were rejected by majority's ruling.
Majority's opinion saw the aims of the fourteenth amendment as a means to "enforce the absolute equality of the two races before the law" but "it could not have been intended to abolish distinctions based upon color, or to enforce social equality". What this means is that the Court limited fourteenth amendment rights to its mere legalities and not the social implications of it.
Justice John Marshall Harlan criticized the ruling by recognizing that Louisiana law was segregationist and perpetuated the idea that colored citizens are inferior, and on top of that, gave it institutional legitimacy: he argued that the government should never "permit the seeds of race hate to be planted under the sanction of law". Segregationist law does nothing but support racial inequality, and should therefore be deemed outright unconstitutional.
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