States involves a full recognition of the dominion and sovereignty of all sister States; and hence section one, Article IV, of the Federal Constitution requires that "full faith and credit shall be given to the public acts, records, and judicial proceedings of other States." Each State, then, in entering the Federal Union, entered into a contract of non-interference with the dominion and prerogatives of other States; and it will not be disputed that the power of taxation is an incident of sovereignty or dominion. The dominion, therefore, of one State for the purpose of taxation over persons, property, business, or the incidents of business, must exclude the dominion of other States over the same persons, property, business, and incidents of business at the same time. Neither in constitutional law in the United States nor in mathematics can the same property, persons, business, or incidents of business occupy two places and two sovereignties at the same time. Hence, the taxation by Connecticut of credits, choses in action, bonds, notes, book accounts, verbal and other contracts, the incidents of actual business transacted in Illinois, must be in legal effect extraterritorial taxation of such business, and so an infringement and violation of the sovereignty of Illinois; or else it must be assumed that business does not include its incidents, or the whole its parts.
Furthermore, if Connecticut has the power of taxing extraterritorial contracts for the loan of money, she has the power to fix any rate and to discriminate as to the States upon whose citizens the burden shall fall; or she may adopt a rate that shall be prohibitory on contracts made by her citizens with citizens of designated States, or citizens of all the States, as her caprice may dictate.
And in this way she may obstruct and to a great extent prevent interstate commerce, which the United States Supreme Court in repeated instances (since the Kirtland case) has decided that the separate State governments can not under the Federal Constitution do either directly or indirectly.
From these considerations, reasoning, and precedents the conclusions of Judge Foster would seem to have been incontrovertible—namely, that "the plaintiff," Kirtland, "was not liable to taxation" in Connecticut "for debts owing to him in Illinois"; and inferentially that, although possibly warranted by the letter of the statute, the act was an attempt on the part of Connecticut to exercise extraterritorial dominion over persons, contracts, or business, and was, therefore, unconstitutional and void. It would also seem to be clear that if property in action (choses in action) is made by fiction of law an entity, having a situs in one State separate from the property which it represents in another State, an opportunity for the grossest inconsistencies will be perpetrated, and the most
