Whether Congress may constitutionally impose a generally applicable federal excise tax on mineral water sold by a State.
Holding
Yes. Congress may tax New York's bottled mineral-water sales because the tax applies equally to state and private vendors and does not discriminate against the States.
Reasoning
Article I gives Congress broad power to lay and collect taxes, and the Constitution expressly limits that power, apart from requirements concerning the manner of taxation, only by prohibiting taxes on exports from a State. Federal tax laws enacted pursuant to that power are supreme law under Article VI.
The Court rejected the old assumption that federal and state instrumentalities enjoy automatically reciprocal tax immunity. The premise that every tax is a forbidden interference because the power to tax includes the power to destroy had been extended too far beyond the discriminatory state tax at issue in McCulloch v. Maryland. Modern doctrine instead recognizes that the National Government is the government of all the States, whose representatives participate in the federal legislative process.
Earlier cases had already sustained federal taxes on state-run liquor businesses and a state-operated street railway. New York's sale of bottled mineral water was not materially different: the State entered a market in which private enterprises also sold the same product, and Congress taxed that source of revenue regardless of the seller's identity.
The tax neither singled New York out nor imposed a special burden on state activity. It reached all vendors of mineral water alike. In those circumstances, requiring New York to bear the same tax as private sellers merely requires the State to contribute to the national government whose constitutional structure enables it to pursue its own policies.