State, local tax deductions mainly benefit the blue states

Charles Lane:

What’s the least defensible special break in the U.S. tax code? With so many distortions to choose from, it’s hard to name just one. If forced to pick, I might say the deduction for state and local taxes, which cost $67 billion in fiscal 2011, according to the congressional Joint Committee on Taxation.

This one overwhelmingly benefits upper-income households in a handful of upper-income states, while rendering the entire nation’s finances less transparent. It’s also a potential source of friction in the “fiscal cliff” negotiations between President Obama and the Republicans (but we’ll get to that in a moment).

Taxpayers have been allowed to deduct state and local income and property taxes since the federal income tax began in 1913. (Sales taxes have at times been deductible, too, but that’ s a relatively minor issue.) The theory is it’s unfair to make people pay twice for the public services they receive. That’s doubtful, though, since, despite some overlap, federal taxes support different services than state and local.

What the deduction does is enable higher-income states and localities to tax — and spend — more than they otherwise would, while shifting some of the cost to other states. It also encourages them to collect revenue in forms that are easier to deduct on federal returns.

Two states, California and New York, reaped almost 30 percent of the deduction’s value in 2009, the latest year for which I could find Internal Revenue Service data. Other states that benefit disproportionately include Connecticut, New Jersey, Illinois, Massachusetts and Maryland.

In 2009, 73 percent of the deduction’s benefits went to taxpayers with annual incomes above $100,000, according to the Congressional Budget Office; fully 20 percent of the benefits went to taxpayers with annual incomes above $1 million.
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States without an income tax wind up subsidizing the profligate blue states like California, New York and Illinois.  Capping this deduction would be a good start for tax reform.  Whether it would force these states to act more responsibly is another matter.