AILSA CHANG, HOST:

You may have heard that yesterday a federal judge allowed a lawsuit against President Trump to move forward. It cleared a very early step. The suit was brought by the attorneys general of Maryland and the District of Columbia. They accused Trump of violating the Emoluments Clause of the Constitution. It bans federal officials from taking gifts or payments from foreign governments and from U.S. states.

AUDIE CORNISH, HOST:

The judge cited an example - the governor of Maine using state funds for a stay at the Trump International Hotel in D.C. Governor LePage was not amused.

(SOUNDBITE OF ARCHIVED RECORDING)

PAUL LEPAGE: The judge that did that is an imbecile. He's a complete imbecile. That's all I can tell you.

CHANG: That was LePage talking to TV station WGME. LePage is a big fan of Trump, by the way. He, too, calls the media a fake news and apparently once referred to himself as Baby Donald.

CORNISH: The governor's visit to the Trump International Hotel was revealed because of reporting by Scott Thistle and Kevin Miller at the Portland Press Herald. Thistle says they figured it out by studying travel receipts they requested from the state. They were heavily redacted. And then the reporters came across a clue.

SCOTT THISTLE: One of the receipts included room service charges where they didn't redact the restaurants. And we were able to kind of cross-reference those to where those restaurants were at, which hotels. In the case of the Trump International Hotel, it was the BLT Prime restaurant that stood out. And when we discovered that was the restaurant inside the hotel, we started to do a couple other checks to cross-reference that.

CORNISH: Was it strange to hear your story cited by this judge in this emoluments case?

THISTLE: I think it was a little bit surprising to both Kevin Miller, my colleague who worked on this, and myself when we saw, you know, the citation. But then again, you know, the governor's office essentially had confirmed that he in fact had stayed there. And subsequently yesterday, the governor again confirmed in his statements to the television station that in fact he had been frequenting the Trump International Hotel.

CORNISH: The emoluments issue is essentially - because of the idea that, you know, officials from the federal government are forbidden from receiving gifts or payments, in this case from states, what questions do you have going forward with your reporting in Maine?

THISTLE: We'd liked to establish, you know, at least how many times has he actually stayed there. The judge certainly inferred that other states may read into that. If they want to curry favor with the president, then they may think about staying at his business enterprises.

CORNISH: How are people reacting to this in the state?

THISTLE: We've had Governor LePage as our governor for seven, going on eight years now. And as you probably know, he's a very colorful figure here. And so I think Maine people are kind of accustomed to the governor. His supporters are very loyal to him. And so they'll say, you know, he's not doing anything unusual; why didn't you guys look at where Democratic governors were staying when they were traveling to Washington? And obviously people who have been the governor's opponent say, you know, this just doesn't pass the straight-face test.

CORNISH: Scott Thistle is a reporter with the "Portland Press Herald." Thank you for speaking with us.

THISTLE: Thank you so much. Transcript provided by NPR, Copyright NPR.