Apportionment of Direct Taxes: The Foul-Up in the Core of the Constitution
Article I, Section 2 of the Constitution requires that direct taxes be apportioned among the states by population. The Founders defined "direct tax" broadly, usually using the term as a synonym for "internal tax" and encompassing all taxes except for customs duties. The Founders expected Congress to use direct taxes. Giving Congress the power to lay internal taxes was a major purpose of the Constitution as a whole.
Apportionment by population, however, turns out to be an absurd and inequitable requirement when the tax base is uneven per capita among the states. With apportionment, tax rates must necessarily be higher in poorer states or in states with a smaller per capita tax base. Where the tax base is especially thin, the tax rates will be prohibitive. The Founders did not see absurdity nor intend that apportionment would hobble any tax.
The early Supreme Court solved the dilemma, when key Founders were still Justices, by interpreting "direct tax" strategically so that no tax was direct if apportionment was unreasonable. That solution was doctrine for one hundred years, and courts need to return to it.
Apportionment has no constitutional weight. Some have described apportionment as an individual right intended to protect accumulated wealth from the force of mere numbers, but that rationale misdescribes the history. Apportionment was a product of the requisition system under the Articles of Confederation, and the formula was written to reach wealth, not to protect it. Apportionment, moreover, was brought over from the Articles into the Constitution solely to help settle a dispute as to the power of the slave states in Congress. With the end of the requisition system and of slavery, apportionment lost its historical rationale and justification.