Article IV, Section 2, Clause 1:
The Citizens of each State shall be entitled to all Privileges and Immunities of Citizens in the several States.
The Privileges and Immunities Clause is self-executory, that is to say, its enforcement is dependent upon the judicial process. It does not authorize penal legislation by Congress. Federal statutes prohibiting conspiracies to deprive any person of rights or privileges secured by state laws, 1 or punishing infractions by individuals of the right of citizens to reside peacefully in the several states and to have free ingress into and egress from such states, 2 have been held void.