Ex post facto laws
Section 13

August 28, 2004

Ex post facto laws--impairment of contracts--irrevocable privileges.
Section 13. That no ex post facto law, nor law impairing the obligation of contracts, or
retrospective in its operation, or making any irrevocable grant of special privileges or immunities,
can be enacted.

Source: Const. of 1875, Art II, § 15.