(CNN) New York, Connecticut, Maryland and New Jersey filed a lawsuit Tuesday claiming last year's tax overhaul violated the constitution by unfairly targeting Democratic states.

The law puts a new cap on how much Americans are allowed to deduct for state and local taxes, or SALT, from their federal bill. Once unlimited, the deduction is now capped at $10,000. Deductions help reduce a person's overall tax bill.

The cap will disproportionately harm high-tax states and their residents, the lawsuit says. It also claims the change in SALT interferes with states' rights to make their own financial decisions.

New York has said the cap will increase New Yorkers' federal taxes by $14.3 billion in 2018.

"New York will not be bullied. This cap is unconstitutional — going well beyond settled limits on federal power to impose an income tax, while deliberately targeting New York and similar states in an attempt to coerce us into changing our fiscal policies and the vital programs they support," said State Attorney General Barbara Underwood in a statement.

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