The St. Louis directory and register :
Article IV—section I.

Full faith and credit shall be given, in each state, to the public
acts, records and judicial proceedings of every other state. And the
Congress may, by penal laws, prescribe the manner in which such
acts, records, and proceedings shall be proved and the effect thereof.

Section II.

1. The citizens of each state shall be entitled to all the privileges
and immunities of citizens in the several states.