The US Army Old Guard, the oldest regiment in the Army, spent at least $26,000 on a party at the Trump International Hotel in DC this past February.

The Old Guard did not use government funds to pay for the event or the deposits required to reserve the space, the Old Guard's spokesman said.

"Questions still remain about why the hotel was selected and the impression given off by holding a military function at Trump's DC hotel, which has been the subject of lawsuits, congressional inquires, and political debate," one legal expert told Insider.

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The US Army ceremonial regiment that escorts the president spent at least $26,000 at President Donald Trump's Trump International Hotel in Washington, DC, for its formal winter ball.

The Old Guard — the 4th battalion of the 3rd US Infantry, which gets its name from being the Army's oldest active-duty regiment — is the president's official escort regiment and performs ceremonial duties, including drum-and-fife shows and keeping vigil at the Tomb of the Unknown Solider in Arlington National Cemetery.

Like most other regiments across the forces, the Old Guard occasionally holds formal events to celebrate its service members. The regiment's winter ball on Feb. 7, 2019, was held at Trump International Hotel in Washington, DC, at a cost of at least $26,000, 1100 Pennsylvania and Citizens for Responsible Ethics in Washington reported. An initial estimate, for 500 guests, put the minimum bill at $48,790 for a three-course plated meal, seven bartenders working three hours each, as well as the rent of the ballroom and additional service fees.

The Trump Organization leases the building the hotel is in from the federal government, and Trump has broken with previous presidents by retaining his ownership of these and other businesses. Ethics watchdogs say Trump may be breaching ethics and the Constitution by profiting off of state and federal governments, as well as foreign governments.

The Old Guard did not use government funds to pay for the event or the deposits required to reserve the space, said the Old Guard's spokesman, Maj. Stephen Von Jett.

"No appropriated funds were used for this event," Von Jett told Insider. "Fundraising for the event began before ticket sales and proceeds from fundraising were used to secure the deposits," he said, mentioning that the fundraisers included candy sales, bake sales, and similar events.

At $80 per ticket, according to an event invitation posted to th eregiment's Facebook, and with 356 attendees, ticket sales would have raised $28,480 to cover the minimum cost of booking the event space. But when asked for the final cost of the event, Von Jett told Insider that because it wasn't an official US military activity, the final cost wasn't recorded.

The Old Guard said the location was chosen by members of the 4th Battalion because it offered a competitive rate and was conveniently located. Asked whether the optics of having an event at the president's luxury hotel concerned the regiment or entered into the decision, Von Jett told Insider, "With no undue command influence, the members of 4th Battalion of the 3rd United States Infantry Regiment, in their personal and private capacity, independently decided to host a private event at the Trump International Hotel Washington."

"The 3rd United States Infantry Regiment assisted the unit with leadership and oversight to ensure their actions were in keeping with all applicable laws and regulations," he added.

However, whoever signed the contract on behalf of the members of the unit organizing the ball used the Old Guard's government address as their physical address on the signatory page.

Ethics issues aside, the regiment's choice remains puzzling, Scott Amey, general counsel at the Project on Government Oversight told Insider.

"If federal funds were not used, the event avoided potential constitutional violations for President Trump," Amey said.

"Questions still remain about why the hotel was selected and the impression given off by holding a military function at Trump's DC hotel, which has been the subject of lawsuits, congressional inquires, and political debate. It could be a simple night out at a trendy DC hotel or a show of support for the commander in chief, but only the organizers can answer that."

The contract, which 1100 Pennsylvania and Citizens for Responsibility and Ethics in Washington (CREW) both obtained through Freedom of Information Act requests, shows most dollar amounts included in the contract, as well as personal information of hotel employees and Old Guard members, have been redacted, making it difficult to know how much was spent on the night out. But in addition to the $26,000 food and beverage minimum, the Trump property tacks on a 24% service charge, adding at least $6,240 to the bill. The minimum also doesn't include services like valet, which could have added a significant amount to the final bill.

On its signature page, the contract includes a section where signatories can indicate whether they are representatives of a foreign government, a foreign government agency, embassy, or political party, a royal family, or sovereign wealth fund, which would ostensibly alert Trump to potential violations of the foreign emoluments clause. No such option exists for members of the US government or a US government entity, although the domestic emoluments clause exists to prevent federal or state governments from contributing to the president's wealth above the amount of his salary.