Hip-hop super-producer Pharrell Williams sent a legal threat to President Donald Trump for playing his hit song “Happy” at a campaign rally on Saturday evening.

In a cease and desist letter, Pharrell Williams’ lawyer claims that the playing of the song amounts to a violation of federal law regarding copyright and trademark infringement. He also argued that the use of the song was inappropriate given the events earlier that day when gunman Robert Bowers killed 11 Jews in what is believed to be an anti-semitic attack.

“On the day of the mass murder of 11 human beings at the hands of a deranged ‘nationalist,’ you played his song ‘Happy’ to a crowd at a political event in Indiana,” read the letter. “There was nothing ‘Happy’ about the tragedy inflicted upon our country on Saturday and no permission was granted for your use of this song for this purpose.”

“Pharrell Williams is the owner of the copyright ‘Happy,’ with the exclusive right to exploit same,” it continued. “Pharrell has not, and will not, grant you permission to publicly broadcast or disseminate any of his music.”

WOWZA. Check out this cease and desist sent by Pharrell Williams to Donald Trump for using “Happy” on “the day of the mass murder of 11 human beings,” as the letter puts it. pic.twitter.com/Mst83Vp0kO — Eriq Gardner (@eriqgardner) October 29, 2018

Williams has previously made no secret of his opposition to Donald Trump, having begged people to vote for Hillary in the 2016 presidential election, despite admitting that she was “dishonest.” The Grammy-winner has since been at the forefront of campaigning against racial injustice, explaining that the real “enemy” lies within the United States.

Ironically, Wiliams has been found guilty of copyright infringement. In 2015, he and singer Robin Thicke were forced to pay out $7.4 million to the children of Marvin Gaye, after they were determined to have copied his 1977 song “Got to Give Up” when producing their hit single “Blurred Lines.”

Of course Pharrell Williams is not the first artist to demand Trump stop playing their music at campaign rallies. Other major artists to do so include The Rolling Stones, Adele, and Queen.

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