Personal attorneys for President Trump and his businesses sued House Oversight Committee chairman Elijah Cummings (D-MD) on Monday in a high-profile bid to stop the body’s investigation into the President’s finances.

Referring to House investigators as “the Democrat Party,” the lawsuit aims to quash a subpoena that Cummings issued to accounting firm Mazars USA for years of financial information from Trump and seven of his companies.

“The Democrat Party, with its newfound control of the U.S. House of Representatives, has declared all-out political war against President Donald J. Trump,” reads the lawsuit, filed in D.C. federal court. “Subpoenas are their weapon of choice.”

Trump argues that Cummings lacks any authority to probe Trump’s finances, saying that “‘oversight’ and ‘transparency,’ in a vacuum, are not legitimate legislative purposes” to justify sending the request to the firm, which they describe as “a private citizen.”

Trump says that House Democrats have sent more than 100 subpoenas since they took hold of the majority in January.

In a statement to TPM, Cummings said that the White House “is engaged in unprecedented stonewalling on all fronts.”

“The President has a long history of trying to use baseless lawsuits to attack his adversaries, but there is simply no valid legal basis to interfere with this duly authorized subpoena from Congress,” the statement reads. “This complaint reads more like political talking points than a reasoned legal brief, and it contains a litany of inaccurate information.”

The president is represented by William Consovoy, a longtime conservative movement attorney who represented Trump in his personal capacity in a lawsuit brought by the attorneys general for Maryland and D.C accusing him of violating the Constitution’s Emoluments clause. Former White House deputy counsel Stefan Passantino — who was charged with monitoring ethics violations — is representing the Trump Org in the case.

Cummings issued a subpoena to Mazars on April 15, the same day that Consovoy and Passantino sent a letter to the firm advising it to ignore the request.

The subpoena demands that Trump’s longtime accountant supply the committee with financial information, annual statements, periodic financial reports, and auditor’s reports for Trump and seven of his companies from 2011 to 2018.

Trump’s attorneys argue in the lawsuit that Cummings “has ignored the constitutional limits on Congress’ power to investigate” because there’s no legislation contemplated by the subpoena. They accuse Cummings of acting as law enforcement and not as a legislator.

“With this subpoena, the Oversight Committee is instead assuming the powers of the Department of Justice, investigating (dubious and partisan) allegations of illegal conduct by private individuals outside of government,” Trump’s team said in the Monday filing. “Its goal is to expose Plaintiffs’ private financial information for the sake of exposure, with the hope that it will turn up something that Democrats can use as a political tool against the President now and in the 2020 election.”

In a separate probe involving Trump’s tax returns, Consovoy accused House Ways and Means Committee Chair Richard Neal (D-MA) of intruding into the President’s private affairs as part of a political witch hunt. In that case, Neal tied the request to Congress’ responsibility to oversee the IRS. The request was linked to the Democrats’ marquee anti-corruption legislation known as H.R. 1, which includes a provision demanding that all presidential and vice-presidential candidates disclose at least ten years of their returns.

Read the lawsuit below: