William Johnson, De Wolf v. Johnson — Opinion of the Court
“ Usury is a mortal taint wherever it exists, and no subterfuge shall be permitted to conceal it from the eye of the law; this is the substance of all the cases, and they only vary as they follow the detours through which they have had to pursue the money lender. But one difficulty presents itself here of no ordinary kind. It is not very easy to discover how the taint of Rhode-Island usury can infuse itself into the veins of a Kentucky contract. The defence would not admit of a moment's reflection if it rested on the direct effects which laws against usury have upon contracts. ”
