What is the Privileges and Immunities Clause?

The Privileges and Immunities Clause is 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." Its basic purpose is to stop states from treating visitors from other states as outsiders when it comes to fundamental rights - a state cannot, for example, let its own citizens own property, access courts, or pursue a trade while categorically shutting out citizens of other states from those same activities. One of the earliest interpretations came from Justice Bushrod Washington riding circuit in Corfield v. Coryell (1823), who described the protected privileges as those "fundamental" rights belonging to citizens of all free governments - among them the right to travel through and reside in other states, to acquire and hold property, and to access the courts on equal terms. The clause does not forbid every distinction between residents and nonresidents; the Supreme Court in Toomer v. Witsell (1948) held that a state must have a substantial reason for treating out-of-state citizens differently and that the discrimination must bear a close relationship to that reason - South Carolina could not charge out-of-state shrimp boat operators a license fee one hundred times higher than in-state operators without such a justification. This Article IV clause is easy to confuse with the similarly named Privileges or Immunities Clause of the Fourteenth Amendment (1868), but they are different provisions: the Article IV clause governs how states must treat citizens of other states relative to their own citizens, while the Fourteenth Amendment clause restricts what a state can do to its own citizens' rights as citizens of the United States. Article IV's clause is the older, interstate-equality guarantee; the Fourteenth Amendment's clause was written after the Civil War to protect basic citizenship rights against a state's own government.