John Marshall Harlan,
Plessy v. Ferguson, 163 U.S. 537…
“ It is quite another thing for government to forbid citizens of the white and black races from traveling in the same public conveyance, and to punish officers of railroad companies for permitting persons of the two races to occupy the same passenger coach. If a State can prescribe, as a rule of civil conduct, that whites and blacks shall not travel as passengers in the same railroad coach, why may it not so regulate the use of the streets of its cities and towns as to compel white citizens to keep on one side of a street and black citizens to keep on the other? ”
