Police stand guard outside the Trump International Hotel on Pennsylvania Avenue in Washington on Jan. 19, the day before President Trump was sworn in. (John Minchillo/Associated Press)

A liberal watchdog group filed a lawsuit against President Trump in federal court on Monday alleging that he is in violation of a little-known constitutional provision that bars him from taking gifts or payments from foreign governments.

The group, Citizens for Responsibility and Ethics in Washington, said that because Trump-owned buildings take in rent, room rentals and other payments from foreign governments, the president has breached the Emoluments Clause. That clause in the Constitution says that “no Person holding any Office of Profit or Trust under [the United States], shall, without the Consent of the Congress, accept of any present, Emolument, Office, or Title, of any kind whatever, from any King, Prince, or foreign State.” It was written out of fear that the young republic’s leaders or ambassadors could be bought off by a richer European power.

The meaning of those words has never truly been tested in court. The watchdog group says the text should be interpreted to mean that Trump’s businesses should cease all business dealings with foreign states.

The clause, the legal complaint says, “is no relic of a bygone era, but rather an expression of insight into the nature of the human condition and the preconditions of self-governance. And applied to Donald J. Trump’s diverse dealings, the text and purpose of the Foreign Emoluments Clause speak as one: this cannot be allowed.”

On Monday morning, Trump rejected the argument behind the lawsuit during a press appearance at the White House. “Without merit,” he said. “Totally without merit”

The group’s proposed lawsuit was first reported Sunday afternoon by the New York Times.

If the lawsuit were to succeed, it could put a major dent in the business of the Trump Organization — whose businesses lease office space to state-owned companies, and whose Pennsylvania Avenue NW hotel rents its ballrooms for foreign embassy parties. The mere process of the suit could prove embarrassing for the president if it drags out details of those business dealings from the Trump Organization’s private files. Norm Eisen, a lawyer working on the case, told the New York Times that he hoped the suit could also produce a copy of Trump’s tax returns, which could detail the business he does with — and the money he owes to — foreign states such as China and Russia.

The law firm Morgan, Lewis and Bockius, which represents Trump, declined to comment. So did Trump’s son Eric Trump, who is among the leaders of the Trump Organization while his father is president. Attempts to reach the White House press office Sunday evening were unsuccessful.

Before the president took office, Sheri Dillon, Trump’s lawyer, said he would transfer management of his businesses to his sons Eric and Donald Trump Jr., along with other executives. The president will not, however, give up his ownership stakes. Dillon said it is incorrect to say that Trump is violating the Emoluments Clause if his company merely does business with a foreign government — taking its money and giving it something of value in return.

“This is not what the Constitution says. Paying for a hotel room is not a gift or a present, and it has nothing to do with an office. It’s not an emolument,” Dillon said then.

In this particular case, the liberal watchdog group’s suit appears likely to face difficult legal hurdles. One would be Dillon’s argument that paying a hotel bill is not a prohibited gift.

Another problem is the question of the watchdog group’s standing to sue. There is a general legal rule that to file suit against someone for wrongdoing, a plaintiff must have suffered some specific harm from that wrongdoing. That’s an issue that has hung over all the discussions of an Emoluments Clause lawsuit: If Trump does violate the Constitution, whom does he hurt?

In this case, the watchdog says its own group was hurt by having to spend so much time monitoring this particular issue.

“CREW has been forced to divert essential and limited resources — including time and money — from other important matters that it ordinarily would have been handling to the Foreign Emoluments Clause issues involving Defendant, which have consumed the attention of the public and the media,” the lawsuit complaint says.

Richard Painter, a law professor at the University of Minnesota, was the chief White House ethics lawyer for President George W. Bush from 2005 to 2007 and is now the vice chairman of CREW’s board of directors. He argued that the group has standing because it has been distracted from its usual focus issues.

“CREW’s whole purpose is about combating corruption in the federal government,” he said. “So up until this point, the two major causes of corruption in the government were the revolving door in Washington and campaign finance. The vast majority of resources were spent on that. It was a two-front war, and now this opens up a third front.”

He added: “The injury to the organization is that it’s much more difficult to accomplish the organization’s mission.”

Other legal scholars have said that claim may not be enough of an injury to let CREW’s case continue. Another theory is that the best-positioned party to sue Trump may be a rival D.C. hotel, if one of them lost out on embassy business because the embassies used the Trump hotel instead. But that would require finding a large D.C. hotel with a willingness to sue the president of the United States at the outset of his term.

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