According to the lawsuit, the allegations against Mr. Asher surfaced in April 2017, when Ms. Oliver received emails that were purportedly from a group of seven anonymous women who belonged to the Society of Children’s Book Writers and Illustrators. The emails claimed that Mr. Asher had used the group’s conferences to prey on women sexually, then threatened them to intimidate them into silence, making them “feel unsafe to attend SCBWI events.”

Mr. Asher has acknowledged having affairs with women he encountered at these conferences, but he maintains that they were consensual and that he never threatened any of the women or offered to help them professionally. In the complaint, Mr. Asher contends that “an individual upset over Plaintiff’s success” was behind the emails to Ms. Oliver, and that in June of 2017, one of the seven anonymous women contacted Ms. Oliver and told her that the allegations made in April were false. But according to the complaint, “no further investigation” was conducted.

The lawsuit further states that Mr. Asher provided the organization with evidence that one of the authors of the emails had “sexually coerced him at a SCBWI Conference” and had been harassing him for more than a decade.

Andrew Baum, a lawyer representing Ms. Oliver and the organization, said that Mr. Asher’s lawsuit “is entirely without merit” and “appears to be an attempt by Asher to repair his name and reputation after it became public that his private actions were inconsistent with his public persona of being an advocate and ally of women.” Mr. Baum noted that after the group received complaints about Mr. Asher’s behavior, Mr. Asher confirmed that he had sexual relationships with multiple members of the writers and illustrators group, and “agreed that he would no longer be on faculty at, present at, or attend, any future SCBWI events.”

In February 2018, the allegations against Mr. Asher erupted into a public controversy, after an article on Medium about sexual harassment in the children’s book world set off a cascade of online accusations against prominent illustrators and authors, including Mr. Asher and the illustrator David Diaz.

That month, Ms. Oliver said in a statement to The Associated Press that the organization had broken with both Mr. Asher and Mr. Diaz. “Claims against them were investigated and, as a result, they are no longer members and neither will be appearing at any SCBWI events in the future,” she said.