The first section [of the Fourteenth Amendment] prohibits the States from abridging the privileges and immunities of citizens of the United States, or unlawfully depriving them of life, liberty, or property, or of denying to any person within their jurisdiction the 'equal' protection of the laws.
I can hardly believe that any person can be found who will not admit that every one of these provisions is just. They are all asserted, in some form or other, in our DECLARATION or organic law. But the Constitution limits only the action of Congress, and is not a limitation on the States. This amendment supplies that defect, and allows Congress to correct the unjust legislation of the States, so far that the law which operates upon one man shall operate equally upon all.
— Representative Thaddeus Stevens of Pennsylvania, speaking before the Joint Committee on Reconstruction in support of the proposed Fourteenth Amendment, May 8, 1866.