Potter Stewart

“ But it is not enough to say that loan sharking is a national problem, for all crime is a national problem. It is not enough to say that some loan sharking has interstate characteristics, for any crime may have an interstate setting. And the circumstance that loan sharking has an adverse impact on interstate business is not a distinguishing attribute, for interstate business suffers from almost all criminal activity, be it shoplifting or violence in the streets. ”

“ Congress surely has power under the Commerce Clause to enact criminal laws to protect the instrumentalities of interstate commerce, to prohibit the misuse of the channels or facilities of interstate commerce, and to prohibit or regulate those intrastate activities that have a demonstrably substantial effect on interstate commerce. ”