George Sutherland, United States v. La Franca — Opinion of the Court
“ This, in reality, is but to say that a person who makes an illegal sale shall be liable to pay a 'tax' in double the amount of the tax imposed by preexisting law for making a legal sale, which existing law renders it impossible to make. A 'tax' is an enforced contribution to provide for the support of government; a 'penalty,' as the word is here used, is an exaction imposed by statute as punishment for an unlawful act. ”
