(CNN) Attorney General William Barr is planning a holiday bash at his boss' hotel in downtown Washington.

The party at the Trump International Hotel, Washington, DC, could wind up costing more than $30,000, according to The Washington Post, which first reported on the party and its details. A Justice Department official told CNN that the party is not an official Justice Department event and will be paid out of Barr's pocket.

Still, it is raising concerns from ethics experts and comes as the Justice Department defends President Donald Trump's businesses in court over claims that they're benefiting unlawfully from his position.

"On the letter of the law, this isn't a violation, however it doesn't look good. That's not nothing when we're talking about the chief law enforcement officer of the country and his private activity," said Liz Hempowicz, the director of public policy at the Project on Government Oversight, a watchdog group.

"It contributes to this idea that you have to be putting money into an entity that will benefit the President -- if not today, then down the road -- personally to stay in his good graces," Hempowicz said.

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