This Article demonstrates how the interaction of a federal statute passed in 1864,1 a case decided by the Supreme Court in 1978,2 and modem technology has legally debarred every state legislature from controlling consumer interest rates in its state-but not from passing laws that appear to do so-and has politically debarred the Congress from setting federal rates to replace the state rates. As a consequence, the elaborate usury laws on the books of most states are only a trompe l'oeil, a "visual deception... rendered in extremely fine detail ... ." The presence of these finely detailed laws gives the illusion that local legislatures are guarding their constituents from high rates, but they are not.
White, James J. "The Usury Trompe L'Oeil." S. C. L. Rev. 51, no. 3 (2000): 445-72.