Slaughter-House Cases

From Conservapedia

In the Slaughter-House Cases (1873), the U.S. Supreme Court rejected an argument that the Privileges and Immunities Clause protected individual rights against encroachment by states.

Specifically, the legislature of Louisiana conferred a special monopoly to a slaughterhouse, and butchers in New Orleans complained. But the Supreme Court essentially rendered the Privileges and Immunities Clause ineffective against state laws except in the rarest of circumstances.