Melania accused Wolff of making “false, defamatory, and lewd statements” in a letter from her attorney Alejandro Brito, saying he had made “extremely salacious” allegations that have reached tens of millions of people worldwide. The letter from Brito demanded that he retract statements including that Epstein had claimed Melania first slept with Trump on the late pedophile’s private jet—or face being sued for at least $1 billion.

Wolff is using so-called anti-SLAPP laws for the case. The laws ban powerful people from using legal actions to shut down journalism, which are known as Strategic Lawsuits Against Public Participation.

Wolff said bringing the case was a “difficult decision” and said, “I did not want to be in a lawsuit, but I also am a journalist and have been one for 40 years.