The income tax amendment was pushed through Congress in 1909 by Sen. Nelson Aldrich, father-in-law of John D. Rockefeller, Jr. and grandfather and namesake of Nelson A. Rockefeller.
The 16th Amendment
Brushaber v. Union Pacific R.R. Co., 240 US 1 (1916) (Entire text of ruling)
The Brushaber decision determined that since the provisions of Article I of the Constitution were not repealed, they are still in full force and effect.
The Sixteenth Amendment to the Constitution of the United States was never ratified by a majority of the sovereign States.
This is the Amendment that allegedly entitled the Federal Agent (government) in the federal territory of Washington, D.C.