Hotel security ordered him to shut off the projections after only a few minutes, but it was enough time for the messages to go viral on social media, garnering thousands of posts on Twitter and Facebook.
"That is one of the big things that I'm trying to do — using our artwork to explain these stories that are tricky," said Bell, an artist and filmmaker based in the District. "If someone can laugh and look at something, and then talk about it."
The projections focused on the Constitution's emoluments clause, which says that no person holding a federal office shall "accept of any present, Emolument, Office, or Title, of any kind whatever, from any King, Prince, or foreign State."
Others read "emoluments welcome here" and "pay Trump bribes here."
Bell said the projections lasted about six minutes, and he was able to keep the projections going while a security guard talked to him about taking them down. His favorite part of the night came, he said, when an open-top tour bus drove by and riders started to cheer.
His stunt was performed hours after a Washington Post story revealed that Trump disclosed highly classified information to Russian diplomats, although Bell said the projections were planned for Monday night long before the news broke. He had been working on the idea and designing the images for more than a month.
"The timing was awesome because it gave us something to look at and enjoy," Bell said. "We did it at the right time because everyone is just so utterly depressed and bummed out with what's going on."
The projections come at an inopportune time for the Trump Organization, which manages the hotel and recently began inviting guests to a new sidewalk cafe.
Earlier that night, about 7:30 p.m., the hotel's general manager pulled guests inside from the cafe to avoid protesters advocating for the rights of those with disabilities. That demonstration traveled along Pennsylvania Avenue in front of the hotel.
Since Trump's election and continued ownership of his stake in the project, the hotel has been dogged by criticism from ethics experts suggesting that he unfairly benefits financially from it. They argue that accepting payments from foreign governments, who rent hotel rooms and meeting spaces, amounts to a violation of the Constitution.
The Trump Organization has pledged to donate profits from foreign leaders to the Treasury at the end of the year. It didn't immediately respond to a request for comment Tuesday.
Leading Democrats have joined ethics experts in questioning why the General Services Administration, which oversees the lease, did not move to terminate the agreement once Trump was elected, because the deal includes a clause barring any "elected official of the government of the United States" from deriving "any benefit" from the project.
In March, the GSA's contracting officer wrote to Eric Trump, the president's son, to say that the lease remained in full compliance, in part, because the president would not benefit from it financially until he left office.
Vandals have repeatedly targeted the hotel. According to police reports, they defaced or damaged the property six times from Election Day through January.
Bell has said that projections are an effective form of protest because they send a message without vandalizing property.
A few weeks ago, he said, he projected an animated version of Attorney General Jeff Sessions's face outside Justice Department headquarters with a magnifying glass, saying "investigate Trump, investigate Russia," in English and Russian.
He also traveled to Harrisburg, Pa., in April to project protest messages against the president as he delivered a speech marking his 100th day in office.