President Donald Trump’s official social media director was found to have violated the Hatch Act on Friday, for invoking his White House position while engaging in a political attack, the Office of Special Counsel wrote in a letter dated June 5.

In a tweet on April 1, White House Social Media Director Dan Scavino urged the constituents of Rep. Justin Amash (R-MI) to vote him out of office.

.@realDonaldTrump is bringing auto plants & jobs back to Michigan. @justinamash is a big liability.#TrumpTrain, defeat him in primary. — Dan Scavino Jr. (@DanScavino) April 1, 2017

Three days later, the progressive watchdog group Citizens for Responsibility and Ethics in Washington (CREW) filed complaints against both Scavino and Amash. The former it accused of using his office — his Twitter account “showed him standing in the Oval Office next to the official presidential flag,” CREW said — for political ends.

The Office of Special Counsel agreed: Scavino, it said, “violated the Hatch Act.”

“Specifically, you alleged on April 1, 2017, Mr. Scavino, while invoking his official position at the White House posted a tweet calling for the defeat of Representative Justin Amash in a primary election,” chief of the Hatch Act Unit, Ana Galindo-Marrone, wrote to CREW.

Galindo-Marrone added that Scavino had been warned, and that her office would consider such activity in the future “willful and knowing violation of the law.”

Amash, CREW alleged in April, used an account he otherwise uses for official purposes to fundraise in response to Scavino:

Bring it on. I'll always stand up for liberty, the Constitution & Americans of every background. You can help here: https://t.co/ECxQGXE5XH. — Justin Amash (@justinamash) April 1, 2017

The Office of Special Counsel did not mention any violations by Amash in its response to CREW. The organization’s executive director noted Friday, in a statement to the Daily Beast, that “OSC has made clear with this ruling that they are going to enforce these important rules and work to keep the government free from inappropriate politics.”

Read OSC’s letter to CREW:

H/t Ryan J. Reilly, Daily Beast