Johnny DeStefano, assistant to President Trump and counselor to the president, and Stephanie Grisham, first lady Melania Trump’s press secretary and communications director, follow the president as they walk from the Oval Office to board Marine One on the South Lawn of the White House on Aug. 24 in Washington, D.C. (Jabin Botsford/The Washington Post)

The first lady’s spokeswoman violated federal law that prohibits public employees from using their official capacity to conduct political activity when she tweeted from her official account a photo and slogan from the 2016 Trump campaign, a federal investigator found.

The investigator issued a warning letter to Stephanie Grisham, first lady Melania Trump’s communications director. The investigator did not find evidence that Grisham engaged in any further prohibited activity and therefore decided not to pursue disciplinary action.

This is the third instance in which a White House official or adviser to President Trump was cited for violation of the Hatch Act, which prohibits public employees from using their official capacity to conduct political activity.

At issue was Grisham’s July 11 post from her official Twitter account in celebration of her third-year anniversary of joining the Trump team during the presidential campaign.

In the tweet, she included a hashtag (#MAGA) representing the 2016 Trump campaign slogan, “Make America Great Again.” Attached to the tweet was a photo of a 2015 rally.

Grisham deleted the post once she became aware that it may have violated the Hatch Act, the letter from the U.S. Office of Special Counsel said. The office is a separate agency from the Justice Department’s special counsel office.

In March, the Office of Special Counsel issued guidance on Hatch Act restrictions after Trump officially announced his reelection campaign. The office noted that the ban on political activity by federal employees is broad and applies to in-person and online communications.

The office said federal employees may not wear or display Trump’s 2016 or 2020 campaign slogans or photos, or use hashtags in support of or opposing Trump, such as #MAGA or #ResistTrump.

Government watchdog group Citizens for Responsibility and Ethics in Washington (CREW) filed the original complaint.

“Despite multiple violations and clear guidance from OSC, the White House refuses to address the pattern of misuse of government offices and resources for political purposes,” CREW’s executive director, Noah Bookbinder, said in a statement. “Because the administration will not act to prevent further use of taxpayer-funded resources for political gain, it is imperative that OSC consider additional measures to prevent these rampant abuses.”

Grisham did not respond to a request for comment.

Earlier this year, the Office of Special Counsel found Kellyanne Conway, a top Trump adviser, violated the Hatch Act on two occasions by making public comments supportive of one candidate and against another ahead of a special U.S. Senate election in Alabama last year. Last year, the office found that White House social media director Dan Scavino Jr. violated the law when he posted on Twitter urging Trump’s supporters to defeat a GOP congressman, Justin Amash, in Michigan.