When President Obama announced a two-year stay of execution for taxpayers on Dec. 7, he made it clear that he intends to spend those two years campaigning for higher marginal tax rates on dividends, capital gains and salaries for couples earning more than $250,000. "I don't see how the Republicans win that argument," said the president.

Despite the deficit commission's call for tax reform with fewer tax credits and lower marginal tax rates, the left wing of the Democratic Party remains passionate about making the U.S. tax system more and more progressive. They claim this is all about payback—that raising the highest tax rates is the fair thing to do because top income groups supposedly received huge windfalls from the Bush tax cuts. As the headline of a Robert Creamer column in the Huffington Post put it: "The Crowd that Had the Party Should Pick up the Tab."

Arguments for these retaliatory tax penalties invariably begin with estimates by economists Thomas Piketty of the Paris School of Economics and Emmanuel Saez of U.C. Berkeley that the wealthiest 1% of U.S. households now take home more than 20% of all household income.

This estimate suffers two obvious and fatal flaws. The first is that the "more than 20%" figure does not refer to "take home" income at all. It refers to income before taxes (including capital gains) as a share of income before transfers. Such figures tell us nothing about whether the top percentile pays too much or too little in income taxes.


In The Journal of Economic Perspectives (Winter 2007), Messrs. Piketty and Saez estimated that "the upper 1% of the income distribution earned 19.6% of total income before tax [in 2004], and paid 41% of the individual federal income tax." No other major country is so dependent on so few taxpayers.

A 2008 study of 24 leading economies by the Organization of Economic Cooperation and Development (OECD) concludes that, "Taxation is most progressively distributed in the United States, probably reflecting the greater role played there by refundable tax credits, such as the Earned Income Tax Credit and the Child Tax Credit. . . . Taxes tend to be least progressive in the Nordic countries (notably, Sweden), France and Switzerland."

The OECD study—titled "Growing Unequal?"—also found that the ratio of taxes paid to income received by the top 10% was by far the highest in the U.S., at 1.35, compared to 1.1 for France, 1.07 for Germany, 1.01 for Japan and 1.0 for Sweden (i.e., the top decile's share of Swedish taxes is the same as their share of income).

A second fatal flaw is that the large share of income reported by the upper 1% is largely a consequence of lower tax rates. In a 2010 paper on top incomes co-authored with Anthony Atkinson of Nuffield College, Messrs. Piketty and Saez note that "higher top marginal tax rates can reduce top reported earnings." They say "all studies" agree that higher "top marginal tax rates do seem to negatively affect top income shares."

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