President Trump on Tuesday afternoon filed a lawsuit as a private citizen against the House Committee on Ways and Means, the New York Attorney General’s office, and the New York Commissioner of Taxation and Finance, in an attempt to block their efforts to disclose his state tax returns.

In May, the New York State Senate passed the TRUST Act, effectively authorizing the state’s department of taxation and finance to share state tax information with a requesting congressional committee—in this case, the ways and means committee. Previously, congressional panels could only file a request for the state’s returns after efforts to gain access through the Treasury Department had failed.

House Judiciary Chairman Jerrold Nadler described the New York bill as a “workaround” to the White House’s ducking of Congressional oversight. “The state return should generally match the federal return and obtaining it from New York State will enable us in Congress to perform our oversight function and maintain the rule of law,” Nadler said.

The TRUST Act created an exception in existing New York law so that the sharing of state tax returns with a congressional committee could be allowed “when the request is made in the furtherance of a legitimate legislative purpose,” according to the New York State Senate press release.

Trump’s lawsuit, filed in the U.S. District Court in Washington, D.C., argues that the committee’s purpose is not legitimate, but malicious. The suit alleges that the defendants worked to pass the TRUST Act with the intent to expose Trump’s tax returns for “political gain.”

“New York legislators admitted that the TRUST Act’s purpose was to help the Committee expose the President’s private tax information for political gain; its purpose was their purpose,” the lawsuit claims. “The TRUST Act also grew out of a larger campaign in New York to uncover and expose the President’s private financial information in the hopes of damaging him politically.”

The suit specifically argues that the reasoning f or the tax returns, given to the state by House Ways and Means Chair Richard Neal (D-MA), is not pertinent to the returns themselves.

“The New York returns have nothing to do with the reason he gave for requesting the President’s federal returns,” the lawsuit reads. “The Chairman is trying to expose the President’s financial information for political gain.”

Rep. Neal is not known for using aggressive tactics; and his cautious approach as chairman of the House Ways and Means Committee—one of the few committees with the power to enforce a subpoena for the president’s tax returns—has irked some of his more progressive colleagues.

Neal initially expressed concern about utilizing the TRUST Act, a fact highlighted by Trump in the lawsuit.

“Despite his initial reluctance, Chairman Neal has recently changed his tune on the TRUST Act,” the lawsuit reads. “Chairman Neal is facing intense pressure from his fellow Democrats to invoke the TRUST Act and obtain the President’s state tax returns. Succumbing to this pressure, the Chairman recently announced that he does not oppose using the TRUST Act and that House counsel was ‘reviewing’ it now.”

Neal was reportedly concerned that requesting the state tax returns through the TRUST Act would interfere with a subpoena for Trump’s returns that he had already—albeit reluctantly—sued the administration to comply with.

The Ways and Means Committee took pains to officially request the president’s returns in order to investigate an IRS’s program to audit all presidents’ tax returns. Trump argues that the IRS review is not the committee’s ultimate goal. “The Chairman is trying to expose the President’s financial information for po litical gain, not to study the IRS’s audit procedures,” according to the lawsuit.

Finally, the lawsuit also claims that the TRUST Act is in violation of the president’s First Amendment rights. “As revealed by its text, history, effect, and stated purposes, the New York Legislature enacted it to discriminate and retaliate against President Trump for his speech and politics,” the lawsuit reads. “This Court should declare it unconstitutional and enjoin its operation.”

New York Attorney General Letitia James responded to the lawsuit on Twitter, vowing Tuesday that she would not back down. “President Trump has spent his career hiding behind lawsuits, and is now suing to hide his taxes. As NY’s chief law enforcement officer, I can assure him no one is above the law,” she wrote. “I’ll vigorously fight to provide the much needed transparency the American people want & deserve.”