South By North Strategies, Ltd.

Writing in The New York Times, economist Robert Frank of Cornell University explains “the problem with flat tax fever.”

The much more serious concern is that a flat tax would reinforce the trends toward greater income inequality that have been seen over the last several decades. As documented by a recent Congressional Budget Office study, the top 1 percent of income recipients in the United States earned 275 percent more in 2007 than they did in 1979, adjusted for inflation, a period when the earnings of middle-income households grew by less than 40 percent. A flat tax would increase inequality by substantially reducing rates on the most prosperous households, while increasing them on low- and middle-income households.
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According to an analysis by the nonpartisan Tax Policy Center, Mr. Cain’s proposal would increase the annual tax bill of a typical family of four earning $50,000 a year by more than $4,000, but would reduce the taxes owed by a similar family earning between $500,000 and $1 million by almost $60,000. The center also estimated that families in the top one-tenth of 1 percent of households would enjoy an average annual tax reduction of nearly $1.4 million under the Cain plan. Similar distributional effects are common under all flat-tax plans, not just Mr. Cain’s.