Mnuchin still backs key provision in GOP tax plan that would hurt (rich) Democrats

Among those in the plan's crosshairs is a long-standing provision that lets you deduct from your reported income the money you pay in state and local taxes on income, real estate or sales of big-ticket items.

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Proponents of the deduction have long argued that, without it, taxpayers would be hit twice for each dollar of income, by their state and by the U.S. Treasury. Opponents argue that the deduction benefits the richest taxpayers at the expense of those with lower incomes, or who don't own a home or make large purchases that carry a big sales tax.