16th Amendment to the United States Constitution

The Sixteenth Amendment (Amendment XVI) to the United States Constitution allows the Congress to levy an income tax without apportioning it among the states or basing it on the United States Census. This amendment exempted income taxes from the constitutional requirements regarding direct taxes, after income taxes on rents, dividends, and interest were ruled to be direct taxes in the court case of Pollock v. Farmers' Loan & Trust Co. (1895). The amendment was adopted on February 3, 1913.

The Congress shall have power to lay and collect taxes on incomes, from whatever source derived, without apportionment among the several States, and without regard to any census or enumeration.

Article I, Section 2, Clause 3:

Representatives and direct taxes shall be apportioned among the several States which may be included within this Union, according to their respective Numbers...

Article I, Section 8, Clause 1:

The Congress shall have Power to lay and collect Taxes, Duties, Imposts and Excises, to pay the Debts and provide for the common Defence and general Welfare of the United States; but all Duties, Imposts and Excises shall be uniform throughout the United States.

Article I, Section 9, Clause 4:

No Capitation, or other direct, Tax shall be laid, unless in proportion to the Census or Enumeration herein before directed to be taken.

This clause basically refers to a tax on property, such as a tax based on the value of land, as well as a capitation.

Article I, Section 9, Clause 5:

No Tax or Duty shall be laid on Articles exported from any State.

Until 1913, customs duties (tariffs) and excise taxes were the primary sources of federal revenue. During the War of 1812, Secretary of the Treasury Alexander J. Dallas made the first public proposal for an income tax, but it was never implemented. The Congress did introduce an income tax to fund the Civil War through the Revenue Act of 1861. It levied a flat tax of three percent on annual income above $800. This act was replaced the following year with the Revenue Act of 1862, which levied a graduated tax of three to five percent on income above $600 and specified a termination of income taxation in 1866. The Civil War income taxes, which expired in 1872, proved to be both highly lucrative and drawing mostly from the more industrialized states, with New York, Pennsylvania, and Massachusetts generating about 60 percent of the total revenue that was collected. During the two decades following the expiration of the Civil War income tax, the Greenback movement, the Labor Reform Party, the Populist Party, the Democratic Party and many others called for a graduated income tax.

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