As President Trump marks the first anniversary of his inauguration, his lawyers are preparing for next week's preliminary arguments in a suit that alleges he is violating the Constitution's anti-corruption provisions, known as the foreign and domestic Emoluments Clauses.

The suit, brought by the District of Columbia and the state of Maryland, contends that people seeking to influence the Trump administration are pumping money into his hotels and golf courses.

Such transactions "could result in the president caring more about where his bread is being buttered than about the policy implications for the country," Karl Racine, attorney general for the District of Columbia, told NPR.

The hearing is scheduled for Thursday in U.S. District Court in Greenbelt, Md. Trump faces two other suits making similar arguments; one involves private business owners who say they are facing unfair competition from Trump-owned properties and the other was brought by Democrats in Congress.

In all three cases, lawyers and other experts have filed arguments over the meaning of "emolument," a now archaic derivative of emolumentum, which is Latin for "profit" or "gain." The foreign Emoluments Clause bars federal officials from taking payments or gifts from foreign governments, unless Congress approves.

The domestic Emoluments Clause prohibits the president from accepting money or gifts from state governments. "It makes sure that states don't have to compete for the favor of the president, by providing the president with things of value," Racine said.

The Maryland and D.C. governments contend that Trump International, the president's luxury hotel near the White House, unfairly takes business away from other venues in Washington and nearby Maryland.

Trump opened the hotel in October 2016, just 13 days before he was elected president. After the election, the hotel quickly became a magnet for lobbyists, foreign diplomats and others.

"We have the finest location and we have the finest building," Trump said at the opening.

The Trump Organization leases the building, known as the historic Old Post Office, from the federal General Services Administration. That is an executive-branch agency which is under control of the president. The lease says no "elected official of the Government of the United States ... shall be admitted to any share or part of this Lease, or to any benefit that may arise therefrom." Nevertheless, GSA has ruled the Trump Organization is in "full compliance."

A year ago, before Trump took office, he and a lawyer told reporters that critics were wrong to invoke the Emoluments Clauses.

"These people are wrong. This is not what the Constitution says," Trump attorney Sheri Dillon said. "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."

And that's what the Justice Department argues when it defends the president.

Legally speaking, this is new territory. There have been some administrative law decisions involving emoluments, but until now, none in federal courts.

"This has never been adjudicated in any court of record in the United States, in our history," constitutional law scholar Seth Barrett Tillman told NPR.

In October, a federal district judge in Manhattan held the first-ever court hearing on a presidential emoluments case. That case had been filed just three days after Trump took office.

It did not go the plaintiffs' way. In a decision that came just before the holidays, a judge said the business people, from the hospitality industry, lacked standing — the necessary legal justification — to sue.

A watchdog group, Citizens for Responsibility and Ethics in Washington, is also a plaintiff in that case. CREW executive director Noah Bookbinder said an appeal is in the works, "so I don't consider that a done deal in any sense."

In the third and most recent lawsuit, some 200 congressional Democrats say Trump has violated the foreign Emoluments Clause by failing to ask Congress for consent, as required by that constitutional provision.

"Congress can't approve what it doesn't know, and this president has been notoriously secret about his financial dealings," said Elizabeth Wydra, president of the Constitutional Accountability Center, which represents the lawmakers. In that case, no court date has been set yet.

Regardless of what happens with these slow-moving legal cases in 2018, the decision that might matter most will be made in the voting booth. If Democrats win control of the House or Senate, they would be able to investigate the emoluments issues and other potential conflicts of interest, with no need to prove their legal standing.

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