In the 1896 case of American Express Company v. Indiana, the Supreme Court ruled in favor of American Express. The state of Indiana had attempted to tax the company for doing business within its borders, arguing that it was a merchant and thus subject to taxation under state law. However, American Express argued that it was not a merchant but rather an express company engaged in interstate commerce and therefore exempt from such taxes due to federal laws regulating interstate commerce. The court agreed with this argument, ruling that as an express company involved primarily in transporting goods across state lines on behalf of customers (rather than buying and selling goods itself), American Express fell under federal jurisdiction for regulation and could not be taxed by individual states like traditional merchants.

The dissenting opinion in the case of AMERICAN EXPRESS COMPANY v. INDIANA, 1896 argued that the state law imposing a tax on express companies was unconstitutional as it violated the Commerce Clause of the U.S Constitution. The justice contended that this clause gives Congress exclusive power to regulate commerce among states and with foreign nations, not individual states. He believed that allowing Indiana to impose such taxes would lead to an untenable situation where each state could levy its own set of taxes on interstate commerce, thereby creating a chaotic and unmanageable system for businesses operating across multiple states. This would also undermine federal authority over interstate commerce by effectively granting regulatory powers intended for Congress alone to individual states.