Source: https://blog.legalsolutions.thomsonreuters.com/legal-research/now-that-your-taxes-are-done/
Timestamp: 2019-04-19 21:17:48+00:00

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2013 is a banner year for legal anniversaries. In January, it was 40 years since Roe v. Wade (410 US 113). March marked 50 years since Gideon v. Wainwright (372 U.S. 335). In July, we’ll celebrate the 150th Anniversary of the 14th Amendment (see U.S.C.A. Const. Amend. XIV-Full Text). And in fact, just last week, on April 8, we celebrated (if that’s the right word) the 100-year anniversary of the 17th Amendment and the direct election of United States Senators (U.S.C.A. Const. Amend. XVII).
But today I want to call your attention to a different legal landmark: last February was the 100 year anniversary of the passage of the 16th Amendment, allowing the federal government to lay direct income taxes. Prior to the 16th Amendment, income taxes had to be apportioned under U.S.C.A. Const. Art. I § 9, cl. 4 of the Constitution. In fact, a prior version of the modern income tax was struck down in Pollock v. Farmer’s Loan & Trust Co., 158 U.S. 601, an event that led directly to the passage of the 16th Amendment.
Given the volume of tax material out there, I was surprised to see that KeyCite has only 2001 references (as of when I write this) for the 16th Amendment (to see them, do a find to U.S.C.A. Const. Amend. XVI and click on citing references). Perhaps this shouldn’t be that surprising; it’s not as though every section of the tax code specifically cites to the amendment for authority. In fact, browsing the references I could only find one statute which cites directly to the amendment: U.C.A. 1953 § 63C-4-107, part of the enacting law for the Utah Constitutional Defense Council.
For more on the background to the 16th amendment, I tried searching for ‘”Direct tax” requiring apportionment’ in All Federal on WestlawNext. Two opinions from the Pollock case were top hits, and the other case hits cases discussing when a tax is and is not direct, such that it must be ‘apportioned.’ There are also a number of law review articles that give more history on the amendment and might be helpful in figuring out if a given tax can be challenged.
For a recent, and well-briefed, case discussing the government’s taxing power under the 16th Amendment, you can look at last year’s Supreme Court healthcare case, National Federation of Independent Business v. Sebelius, 132 S.Ct. 2566.

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