United States v. Chamberlin — Opinion of the Court
“ A tax may or may not be a 'debt' under a particular statute, according to the sense in which the word is found to be used. But whether the government may recover a personal judgment for a tax depends upon the existence of the duty to pay, for the enforcement of which another remedy has not been made exclusive. Whether an action of debt is maintainable depends not upon the question who is the plaintiff or in what manner the obligation was incurred, but it lies whenever there is due a sum either certain or readily reduced to certainty. ”
