The U.S. Supreme Court itself said an 1883 case, “It has been well said that, the property which every man has in his own labor, as it is the original foundation of all other property, so it is the most sacred and inviolable.”
In 1969, the high court ruled: “Whatever may constitute income, therefore, must have the essential feature of gain to the recipient. This was true when the 16th amendment became effective. … If there is no gain, there is no income. … [Income] is not synonymous with receipts.”
And a 1946 case stated, “Reasonable compensation for labor or services rendered is not profit.”
"An income tax is neither a property tax nor a tax on occupations of common right, but is an excise tax."
"The legislature may declare as "privilege" and tax as such for state revenue, those pursuits not matters of common right, but it has no power to declare as a "privilege" and tax for revenue purposes, occupations that are of common right"
Simms v. Ahrens, 271 SW 720 (1925)
"It has been well said that the property which every man has in his own labor, as it is the original foundation of all other property, so it is the most sacred and inviolable. The patrimony of the poor man lies in the strength and dexterity of his own hands, and to hinder his employing this strength and dexterity in what manner he thinks proper, without injury to his neighbor, is a plain violation of this most sacred property."
Butcher's Union Co. v. Crescent City Co., 111 U.S. 746 (1883)
"The power to tax real and personal property and the income from both, there being an apportionment, is conceded: that such tax is a direct tax in the meaning of the Constitution has not been, and, in our judgment, cannot be successfully denied:"
Pollock v. Farmers Loan & Trust, 157 U.S. 429 and 158 U.S. 601 (1895)
"The 16th Amendment does not extend the power of taxation to new or excepted subjects, but merely removes the occasion for apportioning taxes on income among the states. Neither can the tax be sustained as a tax on the person, measured by income. Such a tax would be by nature a capitation rather than an excise."
PECK v. LOWE, 247 U.S. 165(1918).
"The revenue laws are a code or system in regulation of tax assessment and collection. They relate to taxpayers, and not to nontaxpayers. The latter are without scope"
"The 16th Amendment conferred no new power of taxation, but simply prohibited the previous complete and plenary power of income taxation possessed by Congress from the beginning from being taken out of the category of indirect taxation to which it inherently belonged."
STANTON v. BALTIC MINING CO., 240 U.S. 103 (1916).
"The 16th Amendment must be construed in connection with the taxing clauses of the original Constitution and the effect attributed to them before the amendment was adopted."
EISNER v. MACOMBER, 252 U.S. 189 (1920).
United States Court of Claims, Economy Plumbing and Heating v. United States, 470 F.2d 585, at 589 (1972)
"A tax on income is not economically or legally a tax on its source." However, wages, salaries, commissions, and tips (sources) are considered to be "income" for an individual when he lists them as "income" on an IRS tax return form. When he signs the tax form under penalty of perjury, he has made a voluntary oath that his wages, salary, commissions, and tips listed on the return are "income" and that he is subject to the tax."
Graves v. People of the State of New York ex rel O'Keefe, 59 S.Ct. 595 (1939)