By Steve Reilly

Nearly 200 Democratic members of Congress filed a lawsuit against President Trump on Wednesday morning alleging that his continued ties to his business empire violate the U.S. Constitution.

The unprecedented legal action accuses Trump of violating the Emoluments Clause of the U.S. Constitution, which prohibits federal officials from accepting gifts or titles from foreign governments without congressional approval.

The lawsuit will have the greatest number of congressional plaintiffs of any lawsuit against the president in the nation’s history, according to Michigan Rep. John Conyers, the House Judiciary Committee’s top-ranking Democrat.

“We do this not out of any sense of pleasure or partisanship, but because President Trump has left us with no other option,” he said.

Trump’s worldwide organization includes more than 500 business entities spread across at least 20 nations, and includes hotels, golf courses, and apartment buildings, many of which have conducted business with foreign governments. Foreign governments have paid for events at Trump hotels and maintenance fees for condo units in Trump condo buildings.

Although The Trump Organization has pledged to donate foreign government profits from its hotel business to the U.S. Treasury, a company policy document released last month indicates that Trump properties will not verify whether individual customers are representatives of foreign governments on foreign government business because it would be “impractical” and “diminish the guest experience of our brand.”

Sen. Richard Blumenthal, D-Conn., said the litigation is necessary to force Trump to disclose the extent to which his companies are conducting business with foreign government entities, and allow Congress to execute its constitutional obligation to grant or deny permission under the Emoluments Clause.

“We can’t consent to what we don’t know,” he said. “He’s interfering with our constitutional duty.”

Trump and his lawyers have argued that the Emoluments Clause does not apply to fair-market transactions, and that he has taken measures to separate himself from his businesses.

However, the trust in which Trump has placed his assets is run by his sons. Trump is the only beneficiary of the trust and can withdraw funds at any time. He is expected to receive updates on the finances of his business during the course of the presidency. He is the only president in modern history who has not released a copy of his tax returns.

The lawmakers filed the complaint Wednesday morning in U.S. District Court for the District of Columbia. The lawsuit seeks a declaratory judgement from the court declaring that Trump is subject to the Emoluments Clause, and an order enjoining Trump from accepting emoluments.

The Congress members are being represented by the Constitutional Accountability Center, a D.C.-based think tank and law firm “dedicated to fulfilling the progressive promise of our Constitution’s text and history.”

Due to differing House and Senate ethics rules, Senators will split the cost of the legal representation. The Constitutional Accountability Center will provide pro-bono legal services to House members.

The litigation is distinct from an action brought earlier this year by a nonprofit watchdog group, Citizens for Responsibility and Ethics in Washington, which also alleges that Trump has violated the emoluments clause. Separately, the attorneys general of Maryland and the District of Columbia also filed a lawsuit this week on similar grounds.

While legal experts have said the plaintiffs in the prior lawsuits may have difficulty establishing that they have sufficient legal basis to sue, Blumenthal said members of Congress have standing because of their Constitutional duty to consider emoluments matters.

“We have standing because we are injured because we have a duty to vote,” Blumenthal said. “And the President or someone else is denying that duty and that right.”