Trump Taxes GOP Tax Plan
Photo: Getty Images

A provision in the just-passed GOP tax bill will disproportionately increase taxes in largely Democratic states, which may be unconstitutional, a legal expert said on Thursday.

In a post for Newsweek, law professor Michael C. Dorf notes that the new bill reduces the amount of state and local taxes (SALT) that are deductible on your federal return; the cap is now $10,000. That "effectively targets" upper-middle-class taxpayers in states with high SALT, he says. Those include New York, Connecticut, New Jersey, California, Massachusetts, Illinois, Maryland, Rhode Island, and Vermont — all states that reliably vote Democratic.

"What if it turns out that the SALT cap was included in the tax law—which passed the House and Senate without the support of a single Democrat—specifically because its burden would be felt overwhelmingly by residents of heavily Democratic states?" writes Dorf. "If Congress or a state legislature enacted a law with a racially discriminatory impact for the very purpose of disadvantaging a racial minority, that law would be unconstitutional."

The SALT deduction cap could be challenged in court by invoking the Fourteenth Amendment — otherwise known as the equal-protection clause — but it does not prevent the federal government from discriminating against a state, says Dorf. A more pertinent argument might be that enacting higher taxes on a majority-Democrat state violates the First Amendment's guarantee of freedom of political association.


But an even more effective precedent may have been set by, ironically, a Democratic bete noire: The 2013 Supreme Court decision that overturned portions of the Voting Rights Act. In Shelby County v. Holder, Chief Justice John Roberts wrote that the federal law subjected certain states and localities to undue burdens, while not affecting others, and the principle of federalism requires all to be treated equally.

However, it would be necessary to prove that Congress acted with illicit intent in levying the SALT cap: Many other tax laws affect certain states more than others. "Were a court to order discovery aimed at uncovering Republican congressional defendants’ true motives, they could probably get away with pointing to some non-partisan rationale for capping SALT deductibility," writes Dorf. "The key phrase there is 'get away with.' Due to difficulties of proof, the courts probably won’t end up ruling that the SALT deductibility cap violates the First Amendment or a core principle of federalism."