may act "rationally" to prevent private actors from imposing "badges and incidents of servitude". The Joneses were a black couple in St. Louis County, Missouri, who sued a real estate company for refusing to sell them a house. The Court held: <blockquote>Congress has the power under the Thirteenth Amendment rationally to determine what are the badges and the incidents of slavery, and the authority to translate that determination into effective legislation. ... this Court recognized long ago that, whatever else they may have encompassed, the badges and incidents of slavery—its "burdens and disabilities"—included restraints upon "those fundamental rights which are the essence of civil freedom, namely, the same right ... to inherit, purchase, lease, sell and convey property, as is enjoyed by white citizens." Civil Rights Cases, 109 U. S. 3, 109 U. S. 22.<ref>'Jones v. Alfred H. Mayer Co., 392 U.S. 409 (1968)</ref></blockquote> Just as the Black Codes, enacted after the Civil War to restrict the free exercise of those rights, were substitutes for the slave system, so the exclusion of Negroes from white communities became a substitute for the Black Codes. And when racial discrimination herds men into ghettos and makes their ability to buy property turn on the color of their skin, then it too is a relic of slavery. Negro citizens, North and South, who saw in the Thirteenth Amendment a promise of freedom—freedom to "go and come at pleasure" and to "buy and sell when they please"—would be left with "a mere paper guarantee" if Congress were powerless to assure that a dollar in the hands of a Negro will purchase the same thing as a dollar in the hands of a white man. At the very least, the freedom that Congress is empowered to secure under the Thirteenth Amendment includes the freedom to buy whatever a white man can buy, the right to live wherever a white man can live. If Congress cannot say that being a free man means at least this much, then the Thirteenth Amendment made a promise the Nation cannot keep. The Court in Jones reopened the issue of linking racism in contemporary society to the history of slavery in the United States. The Jones precedent has been used to justify Congressional action to protect migrant workers and target sex trafficking. The direct enforcement power found in the Thirteenth Amendment contrasts with that of the Fourteenth, which allows only responses