The Tax Cuts and Jobs Act, Pub. L. No. 115-97, limits an individual's deduction under IRC §164 for the total amount of state and local taxes (SALT) paid during the calendar year to $10,000 ($5,000 for a married individual filing a separate return). State and local tax payments exceeding those amounts aren't deductible. This new limitation applies to taxable years 2018 through 2025.

State law workarounds. Responding to this new limitation, New York, New Jersey, Connecticut and Maryland enacted laws allowing their taxpayers to make transfers to funds controlled by state or local governments, or other transferees specified by the state, in exchange for credits against the state or local taxes that taxpayers are required to pay.

These laws allow the states' taxpayers to characterize their transfers as fully deductible charitable contributions for federal income tax purposes, while using the same transfers to satisfy state and local tax liabilities.

Proposed regulations thwart state plans to work around the $10,000 limit on state and local tax deductions. REG-112176-18.

New York and the three other states sued to invalidate the $10,000 deductibility ceiling on state and local taxes. The actions seek declaratory and injunctive relief on a host of grounds including:

• The new cap effectively eviscerates the SALT deduction, overturning more than 150 years of precedent by drastically curtailing the deduction's scope. As the drafters of the Sixteenth Amendment and every subsequent Congress have understood, the SALT deduction is essential to prevent the federal tax power from interfering with the States' sovereign authority to make their own choices about whether and how much to invest in their own residents, businesses, infrastructure, and more.

• A SALT deduction has been a part of every federal income tax law since the first federal income tax was enacted in 1861.

• The new cap on the SALT deduction is unprecedented, unlawful, and will cause significant and disproportionate injury to the Plaintiff States and their residents.

• The new cap will significantly increase the amount of taxes residents in Plaintiff States will pay to the federal government.

• The new cap on the SALT deduction is likely to substantially decrease home values in the Plaintiff States, hurting both in-state homeowners and the Plaintiff States themselves.

Latest development. The federal government asks the U.S. District Court, Southern District of New York to dismiss the four states' lawsuit on these grounds:

The States' complaint posits a radical theory—namely, that the Sixteenth Amendment, rather than expanding Congress's taxing power, severely cabined that power, granting states the right to limit federal taxation. Accepting these arguments would require the court to hold:

• First, that the text of the Sixteenth Amendment, without actually saying so, requires “a deduction for all or a significant portion of state and local taxes.”

• Second, that the Sixteenth Amendment allows states to increase their tax rates without limit, and the federal government must provide an unlimited corresponding deduction.

• Third, that generalized state sovereignty principles override Congress's constitutional taxation power. The complaint suggests that such principles prohibit any federal legislation that might make it more difficult for a state to “set [its] legislative agenda.”

• Fourth, that the spheres of operation of federal and state taxation must be “different and not conflicting.”

The States can point to no constitutional text supporting these theories, so they instead write a revisionist history about the purpose of the Sixteenth Amendment.

At bottom, the States identify no constitutional provision supporting their theories.

The court need not reach the merits of their claims, however, because there are threshold jurisdictional issues barring this suit.

State of New York (and Connecticut, Maryland, New Jersey) v. Department of Treasury, U.S. District Court, SDNY, Civil Action No. 18-???-6427

Be careful out there. Commentators believe the lawsuit to invalidate the SALT limitation will be unsuccessful. The IRS will deny claimed charitable deductions for what are, in effect, required tax payments—and impose interest and penalties.

Conrad Teitell is a principal at Cummings & Lockwood in Stamford, Conn.