Maryland Attorney General E. Brian Frosh canserve subpoenas requiring the Trump Organization to preserve documents in an “emoluments” lawsuit he and the D.C. attorney general filed.(Jonathan Newton / The Washington Post)

A federal judge Tuesday ordered President Trump’s business to preserve records related to a lawsuit brought by the Democratic attorneys general from Maryland and the District of Columbia that allege his private company has violated anti-corruption clauses in the Constitution.

With the ruling, D.C. Attorney General Karl A. Racine and Maryland Attorney General Brian E. Frosh are now permitted toserve subpoenas requiring the Trump Organization to preserve documents if the court allows the two sides to seek evidence from one another.

The decision by Judge Peter J. Messitte is a small advancement in one of the most high-profile attempts to get a court to consider a case on the emoluments clauses of the Constitution, which bars the president from accepting gifts or payments from foreign or state governments.

“This ruling is an important first step in our litigation against President Trump for unlawfully receiving emoluments from foreign and domestic governments,” Racine said in a statement.

No court has considered an emoluments case previously, and some legal experts doubt any judge will allow such cases to proceed.

Because Trump continues to benefit financially from his hotel, resort and golf properties — in some cases from clients affiliated with foreign governments — Frosh and Racine alleged in their June complaint that Trump had committed “unprecedented constitutional violations.”

State spending that benefits the president may be considered a violation of the domestic emolument clause, which says the president “shall not receive” any emolument, other than fixed compensation, from “the United States, or any of them.”

That provision brings into question spending by state officials at Trump properties, which may be more likely as the properties host an increasing number of fundraisers and campaign events on behalf of Republican congressional candidates.

For instance, on Tuesday night at the Trump International Hotel in Washington, Texas Attorney General Ken Paxton was spotted among Trump campaign supporters and volunteers attending a party celebrating Trump’s 2016 campaign victory.

Paxton’s office did not immediately respond to a question about whether state money was spent at the hotel or if Paxton stayed in the hotel overnight. Trump campaign officials did not respond to requests for comment.

Justice Department attorneys asked Messitte to dismiss the case in September and in a filing last month, agency attorneys argued that no evidence should be sought “through subpoenas or other mechanisms” in the meantime.

Justice Department officials declined to comment. The Trump Organization, now run by Trump’s adult sons, Donald Trump Jr. and Eric Trump, has said it plans to donate profits from foreign governments booked at the president’s D.C. hotel at year’s end.

Racine and Frosh’s case is one of a handful of suits brought by states, watchdog groups or businesses competing with the Trump Organization over emoluments. In January, the Citizens for Responsibility and Ethics in Washington (CREW), a watchdog group, brought a similar suit and Cork Wine Bar, a D.C. restaurant, sued Trump in March, alleging the new Trump D.C. hotel unfairly benefits from the president’s White House position.

Changes to Trump’s business could affect the cases as they proceed. Owners of the former Trump International Hotel and Tower in Toronto parted ways with the Trump Organization in the summer, and the owners of Trump SoHo plan to do so at year’s end. Two days after the SoHo breakup was announced, Justice Department attorneys wrote to the judge in the CREW case saying the change undermined the argument about unfair competition and was “further reason” the court should dismiss the case.

Ann E. Marimow and Rachel Weiner contributed to this report.