Article 1 Section 9 of the U.S. Constitution limits the taxation powers of Congress, saying:
“No capitation, or other direct, tax shall be laid, unless in proportion to the census or enumeration herein before directed to be taken.”
This simply outlaws income taxes.
The Fifth Amendment to the U.S. Constitution ends:
“…nor be deprived of life, liberty, or property, without due process of law; nor shall private property be taken for public use, without just compensation.”
This says the government may not deprive the accused of natural rights, and that the government cannot take private property without paying for it.
Some would argue that the last part does not apply to income or labor, but only to physical property, such as land or belongings. Let it be recognized, however, that land and belongings are nothing more than tangible storages of income and labor. Moreover, it would be absurd to suggest that a man’s labor is not his property, and therefore, according to this amendment, the government may not take a person’s labor (income) for public use without just compensation.
The Sixteenth Amendment grants Congress the authority to tax incomes:
“Congress shall have the 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.”
This is a clear contradiction of Article 1 Section 9.
Section 1 of the Thirteenth Amendment:
“Neither slavery nor involuntary servitude, except as a punishment for crime whereof the party shall have been duly convicted, shall exist within the United States, or any place subject to their jurisdiction.”
This prohibits any entity from forcing any individual to work by force or by state-imposed coercion (or threats thereof), unless as a punishment for a crime.
The income tax is not technically a form of involuntary servitude to the government, because the government does not force anyone to work. However, under the income tax, everyone who chooses to work is forced to work for the government, so the spirit of the amendment may very well apply to outlawing the income tax.
There are certainly those who feel like slaves to the government, because the government takes a great part of the fruits of their labor; but technically, this is not true, because they may always choose not to work, and while this choice may be a threat to their survivals, it is not a direct threat from government. This unhappy choice, however, contains the implicit threat: “work for the government, or die.” So it is not completely clear whether the income tax qualifies as universal slavery, which would be prohibited by this amendment.
When this amendment ended slavery, note that it literally scribbled out all other portions of the Constitution that contradicted the new amendment. Note also that, when the Sixteenth Amendment was written to allow income taxes, none of the previous portions that outlaw such taxes were removed from the Constitution.
This practical difference, I believe, shows the spirit with which these two amendments passed. When slavery was ended, the public was quick to remove from the record all evidence of its existence, because slavery was a stain on liberty and justice; it was an embarrassment to an otherwise proud society of free individuals. But when the income tax was instituted, the amendment allowing it was the embarrassment to freedom, and all else in the Constitution that contradicted it was left to bear, so the people could still call it their own, and perhaps retain some nostalgic feeling of what it was to be free.